diff --git a/avatar/admin.py b/avatar/admin.py
index fafcf0e..a6486ce 100644
--- a/avatar/admin.py
+++ b/avatar/admin.py
@@ -3,12 +3,12 @@ from django.utils.translation import ugettext_lazy as _
 
 from avatar.models import Avatar
 from avatar.templatetags.avatar_tags import avatar
-
+from avatar.util import User
 
 class AvatarAdmin(admin.ModelAdmin):
     list_display = ('get_avatar', 'user', 'primary', "date_uploaded")
     list_filter = ('primary',)
-    search_fields = ('user__username',)
+    search_fields = ('user__%s' % getattr(User, 'USERNAME_FIELD', 'username'),)
     list_per_page = 50
 
     def get_avatar(self, avatar_in):
diff --git a/avatar/models.py b/avatar/models.py
index a6d0b4d..95871b2 100644
--- a/avatar/models.py
+++ b/avatar/models.py
@@ -9,7 +9,7 @@ from django.utils.translation import ugettext as _
 from django.utils.encoding import smart_str
 from django.db.models import signals
 
-from django.contrib.auth.models import User
+from avatar.util import User, get_username
 
 try:
     from cStringIO import StringIO
@@ -40,10 +40,10 @@ avatar_storage = get_storage_class(AVATAR_STORAGE)()
 def avatar_file_path(instance=None, filename=None, size=None, ext=None):
     tmppath = [AVATAR_STORAGE_DIR]
     if AVATAR_HASH_USERDIRNAMES:
-        tmp = hashlib.md5(instance.user.username).hexdigest()
-        tmppath.extend([tmp[0], tmp[1], instance.user.username])
+        tmp = hashlib.md5(get_username(instance.user)).hexdigest()
+        tmppath.extend([tmp[0], tmp[1], get_username(instance.user)])
     else:
-        tmppath.append(instance.user.username)
+        tmppath.append(get_username(instance.user))
     if not filename:
         # Filename already stored in database
         filename = instance.avatar.name
diff --git a/avatar/templates/avatar/add.html b/avatar/templates/avatar/add.html
index a62df6c..7a04b34 100644
--- a/avatar/templates/avatar/add.html
+++ b/avatar/templates/avatar/add.html
@@ -1,5 +1,6 @@
 {% extends "avatar/base.html" %}
 {% load i18n avatar_tags %}
+{% load url from future %}
 
 {% block content %}
     <p>{% trans "Your current avatar: " %}</p>
@@ -7,7 +8,7 @@
     {% if not avatars %}
         <p>{% trans "You haven't uploaded an avatar yet. Please upload one now." %}</p>
     {% endif %}
-    <form enctype="multipart/form-data" method="POST" action="{% url avatar_add %}">
+    <form enctype="multipart/form-data" method="POST" action="{% url 'avatar_add' %}">
         {{ upload_avatar_form.as_p }}
         <p>{% csrf_token %}<input type="submit" value="{% trans "Upload New Image" %}" /></p>
     </form>
diff --git a/avatar/templates/avatar/change.html b/avatar/templates/avatar/change.html
index 321da0d..7e7b3d2 100644
--- a/avatar/templates/avatar/change.html
+++ b/avatar/templates/avatar/change.html
@@ -1,5 +1,6 @@
 {% extends "avatar/base.html" %}
 {% load i18n avatar_tags %}
+{% load url from future %}
 
 {% block content %}
     <p>{% trans "Your current avatar: " %}</p>
@@ -7,14 +8,14 @@
     {% if not avatars %}
         <p>{% trans "You haven't uploaded an avatar yet. Please upload one now." %}</p>
     {% else %}
-        <form method="POST" action="{% url avatar_change %}">
+        <form method="POST" action="{% url 'avatar_change' %}">
             <ul>
                 {{ primary_avatar_form.as_ul }}
             </ul>
             <p>{% csrf_token %}<input type="submit" value="{% trans "Choose new Default" %}" /></p>
         </form>
     {% endif %}
-    <form enctype="multipart/form-data" method="POST" action="{% url avatar_add %}">
+    <form enctype="multipart/form-data" method="POST" action="{% url 'avatar_add' %}">
         {{ upload_avatar_form.as_p }}
         <p>{% csrf_token %}<input type="submit" value="{% trans "Upload New Image" %}" /></p>
     </form>
diff --git a/avatar/templates/avatar/confirm_delete.html b/avatar/templates/avatar/confirm_delete.html
index 5c54a7d..373131d 100644
--- a/avatar/templates/avatar/confirm_delete.html
+++ b/avatar/templates/avatar/confirm_delete.html
@@ -1,13 +1,14 @@
 {% extends "avatar/base.html" %}
 {% load i18n %}
+{% load url from future %}
 
 {% block content %}
     <p>{% trans "Please select the avatars that you would like to delete." %}</p>
     {% if not avatars %}
-        {% url avatar_change as avatar_change_url %}
+        {% url 'avatar_change' as avatar_change_url %}
         <p>{% blocktrans %}You have no avatars to delete. Please <a href="{{ avatar_change_url }}">upload one</a> now.{% endblocktrans %}</p>
     {% else %}
-        <form method="POST" action="{% url avatar_delete %}">
+        <form method="POST" action="{% url 'avatar_delete' %}">
             <ul>
                 {{ delete_avatar_form.as_ul }}
             </ul>
diff --git a/avatar/templates/notification/avatar_friend_updated/notice.html b/avatar/templates/notification/avatar_friend_updated/notice.html
index 093c2c1..c2ba8bc 100644
--- a/avatar/templates/notification/avatar_friend_updated/notice.html
+++ b/avatar/templates/notification/avatar_friend_updated/notice.html
@@ -1,2 +1,2 @@
-{% load i18n %}{% url profile_detail username=user.username as user_url %}
-{% blocktrans with user as avatar_creator and avatar.get_absolute_url as avatar_url %}<a href="{{ user_url }}">{{ avatar_creator }}</a> has updated their avatar <a href="{{ avatar_url }}">{{ avatar }}</a>.{% endblocktrans %}
\ No newline at end of file
+{% load i18n %}{% load url from future %}{% url 'profile_detail' username=user.username as user_url %}{# TODO: support custom user models via get_username; actually, is this template even used anymore? #}
+{% blocktrans with user as avatar_creator and avatar.get_absolute_url as avatar_url %}<a href="{{ user_url }}">{{ avatar_creator }}</a> has updated their avatar <a href="{{ avatar_url }}">{{ avatar }}</a>.{% endblocktrans %}
diff --git a/avatar/templatetags/avatar_tags.py b/avatar/templatetags/avatar_tags.py
index 32cede3..fbb21df 100644
--- a/avatar/templatetags/avatar_tags.py
+++ b/avatar/templatetags/avatar_tags.py
@@ -7,11 +7,10 @@ from django.template.loader import render_to_string
 from django.utils.translation import ugettext as _
 from django.core.urlresolvers import reverse
 
-from django.contrib.auth.models import User
-
 from avatar.settings import (AVATAR_GRAVATAR_BACKUP, AVATAR_GRAVATAR_DEFAULT,
                              AVATAR_DEFAULT_SIZE, AVATAR_GRAVATAR_BASE_URL)
-from avatar.util import get_primary_avatar, get_default_avatar_url, cache_result
+from avatar.util import (
+    get_primary_avatar, get_default_avatar_url, cache_result, User, get_user)
 from avatar.models import Avatar
 
 register = template.Library()
@@ -40,7 +39,7 @@ def avatar_url(user, size=AVATAR_DEFAULT_SIZE):
 def avatar(user, size=AVATAR_DEFAULT_SIZE, **kwargs):
     if not isinstance(user, User):
         try:
-            user = User.objects.get(username=user)
+            user = get_user(user)
             alt = unicode(user)
             url = avatar_url(user, size)
         except User.DoesNotExist:
diff --git a/avatar/tests.py b/avatar/tests.py
index 74938ab..6d233d8 100644
--- a/avatar/tests.py
+++ b/avatar/tests.py
@@ -4,10 +4,8 @@ from django.test import TestCase
 from django.core.urlresolvers import reverse
 from django.conf import settings
 
-from django.contrib.auth.models import User
-
 from avatar.settings import AVATAR_DEFAULT_URL, AVATAR_MAX_AVATARS_PER_USER
-from avatar.util import get_primary_avatar
+from avatar.util import get_primary_avatar, User
 from avatar.models import Avatar
 
 try:
diff --git a/avatar/urls.py b/avatar/urls.py
index 1fbe017..3635341 100644
--- a/avatar/urls.py
+++ b/avatar/urls.py
@@ -7,6 +7,6 @@ urlpatterns = patterns(
     url(r'^change/$', 'change', name='avatar_change'),
     url(r'^delete/$', 'delete', name='avatar_delete'),
     url(r'^render_primary/(?P<user>[\w\d\.\-_]{3,30})/(?P<size>[\d]+)/$', 'render_primary', name='avatar_render_primary'),
-    url(r'^list/(?P<username>[\+\w]+)/$', 'avatar_gallery', name='avatar_gallery'),
-    url(r'^list/(?P<username>[\+\w]+)/(?P<id>[\d]+)/$', 'avatar', name='avatar'),
+    url(r'^list/(?P<username>[\+\w\@\.]+)/$', 'avatar_gallery', name='avatar_gallery'),
+    url(r'^list/(?P<username>[\+\w\@\.]+)/(?P<id>[\d]+)/$', 'avatar', name='avatar'),
 )
diff --git a/avatar/util.py b/avatar/util.py
index 2e9382c..3474ca7 100644
--- a/avatar/util.py
+++ b/avatar/util.py
@@ -5,20 +5,41 @@ from django.core.cache import cache
 from django.utils.encoding import smart_str
 from django.template.defaultfilters import slugify
 
-from django.contrib.auth.models import User
+try:
+    from django.contrib.auth import get_user_model
+except ImportError:
+    from django.contrib.auth.models import User
+    custom_user_model = False
+else:
+    User = get_user_model()
+    custom_user_model = True
 
 from avatar.settings import (AVATAR_DEFAULT_URL, AVATAR_CACHE_TIMEOUT,
                              AUTO_GENERATE_AVATAR_SIZES, AVATAR_DEFAULT_SIZE)
 
 cached_funcs = set()
 
+def get_username(user):
+    """ Return username of a User instance """
+    if hasattr(user, 'get_username'):
+        return user.get_username()
+    else:
+        return user.username
+
+def get_user(username):
+    """ Return user from a username/ish identifier """
+    if custom_user_model:
+        return User.objects.get_by_natural_key(username)
+    else:
+        return User.objects.get(username=username)
+
 
 def get_cache_key(user_or_username, size, prefix):
     """
     Returns a cache key consisten of a username and image size.
     """
     if isinstance(user_or_username, User):
-        user_or_username = user_or_username.username
+        user_or_username = get_username(user_or_username)
     key = u'%s_%s_%s' % (prefix, user_or_username, size)
     return u'%s_%s' % (slugify(key)[:100],
                        hashlib.md5(smart_str(key)).hexdigest())
@@ -70,7 +91,7 @@ def get_default_avatar_url():
 def get_primary_avatar(user, size=AVATAR_DEFAULT_SIZE):
     if not isinstance(user, User):
         try:
-            user = User.objects.get(username=user)
+            user = get_user(user)
         except User.DoesNotExist:
             return None
     try:
diff --git a/avatar/views.py b/avatar/views.py
index 658bcc2..5910681 100644
--- a/avatar/views.py
+++ b/avatar/views.py
@@ -7,13 +7,13 @@ from django.views.decorators.csrf import csrf_exempt
 
 from django.contrib import messages
 from django.contrib.auth.decorators import login_required
-from django.contrib.auth.models import User
 
 from avatar.forms import PrimaryAvatarForm, DeleteAvatarForm, UploadAvatarForm
 from avatar.models import Avatar
 from avatar.settings import AVATAR_MAX_AVATARS_PER_USER, AVATAR_DEFAULT_SIZE
 from avatar.signals import avatar_updated
-from avatar.util import get_primary_avatar, get_default_avatar_url
+from avatar.util import (
+    get_primary_avatar, get_default_avatar_url, User, get_user)
 
 
 def _get_next(request):
@@ -173,7 +173,10 @@ def delete(request, extra_context=None, next_override=None, *args, **kwargs):
 
 
 def avatar_gallery(request, username, template_name="avatar/gallery.html"):
-    user = get_object_or_404(User, username=username)
+    try:
+        user = get_user(username)
+    except User.DoesNotExist:
+        raise Http404
     return render_to_response(template_name, {
         "other_user": user,
         "avatars": user.avatar_set.all(),
@@ -181,7 +184,10 @@ def avatar_gallery(request, username, template_name="avatar/gallery.html"):
 
 
 def avatar(request, username, id, template_name="avatar/avatar.html"):
-    user = get_object_or_404(User, username=username)
+    try:
+        user = get_user(username)
+    except User.DoesNotExist:
+        raise Http404
     avatars = user.avatar_set.order_by("-date_uploaded")
     index = None
     avatar = None
diff --git a/docs/usage.txt b/docs/usage.txt
index 73785c6..327e8ba 100644
--- a/docs/usage.txt
+++ b/docs/usage.txt
@@ -28,7 +28,7 @@ that are required.  A minimal integration can work like this:
 3.  Somewhere in your template navigation scheme, link to the change avatar
     page::
     
-        <a href="{% url avatar_change %}">Change your avatar</a>
+        <a href="{% url 'avatar_change' %}">Change your avatar</a>
 
 4.  Wherever you want to display an avatar for a user, first load the avatar
     template tags::
@@ -135,4 +135,4 @@ Management Commands
 This application does include one management command: ``rebuild_avatars``.  It
 takes no arguments and, when run, re-renders all of the thumbnails for all of
 the avatars for the pixel sizes specified in the ``AUTO_GENERATE_AVATAR_SIZES``
-setting.
\ No newline at end of file
+setting.
diff --git a/setup.py b/setup.py
index df35977..2df6037 100644
--- a/setup.py
+++ b/setup.py
@@ -33,7 +33,7 @@ that are required.  A minimal integration can work like this:
 3.  Somewhere in your template navigation scheme, link to the change avatar
     page::
     
-        <a href="{% url avatar_change %}">Change your avatar</a>
+        <a href="{% url 'avatar_change' %}">Change your avatar</a>
 
 4.  Wherever you want to display an avatar for a user, first load the avatar
     template tags::
@@ -92,12 +92,12 @@ template rendering system:
 
 ``{% avatar_url user [size in pixels] %}``
     Renders the URL of the avatar for the given user.  User can be either a
-    ``django.contrib.auth.models.User`` object instance or a username.
+    ``django.contrib.auth.get_user_model()`` object instance or a username.
 
 ``{% avatar user [size in pixels] %}``
-    Renders an HTML ``img`` tag for the given user for the specified size.  User
-    can be either a ``django.contrib.auth.models.User`` object instance or a
-    username.
+    Renders an HTML ``img`` tag for the given user for the specified size. User
+    can be either a ``django.contrib.auth.get_user_model()`` object instance
+    or a username.
 
 ``{% render_avatar avatar [size in pixels] %}``
     Given an actual ``avatar.models.Avatar`` object instance, renders an HTML