diff -r 4fe4ce7e2544 -r 979dbe0cade3 interfaces.py
--- a/interfaces.py	Thu Nov 20 11:51:28 2008 +0100
+++ b/interfaces.py	Fri Nov 21 17:36:42 2008 +0100
@@ -232,3 +232,9 @@
         (returns None for default)
         """
         
+class IFeed(Interface):
+    """interface for entities with rss flux"""
+    
+    def rss_feed_url(self):
+        """return an url which layout sub-entities item
+        """