http://twitteravatar.appspot.com/users/avatar/screeen_name
Example:
<img src="http://twitteravatar.appspot.com/users/avatar/dacort"> »
Only have a user id from those social graph methods? No problem.
http://twitteravatar.appspot.com/users/avatar?user_id=99723
What's that? You need a different size? Got that covered.
http://twitteravatar.appspot.com/users/avatar/dacort/mini
Sizes available are mini, normal, bigger and original.
An example for user id: http://twitteravatar.appspot.com/users/avatar/bigger?user_id=99723
Example Applications:
FolloWar | Commonality | FollowMinder