Index: tests/regressiontests/defaultfilters/tests.py
===================================================================
--- tests/regressiontests/defaultfilters/tests.py	(revision 6710)
+++ tests/regressiontests/defaultfilters/tests.py	(working copy)
@@ -37,6 +37,8 @@
 u'13.1031'
 >>> floatformat(u'foo', u'bar')
 u''
+>>> floatformat(None)
+u''
 
 >>> addslashes(u'"double quotes" and \'single quotes\'')
 u'\\"double quotes\\" and \\\'single quotes\\\''
Index: django/template/defaultfilters.py
===================================================================
--- django/template/defaultfilters.py	(revision 6710)
+++ django/template/defaultfilters.py	(working copy)
@@ -89,7 +89,7 @@
     """
     try:
         f = float(text)
-    except ValueError:
+    except (ValueError, TypeError):
         return u''
     try:
         d = int(arg)