gravatar does a wonderful job with email avatars, but they have failed to support OpneIDs. I built a simple interface for associating your OpenID with an email, which is then proxied to gravatar.
So I give you OpenID Avatar.
Simply change your gravatar urls to use http://paulisageek.com/openidavatar/avatar/ instead of http://www.gravatar.com/avatar/ Then you can use md5s of openids in addition to emails. If you want to use them both, just set the email_md5 param as well. See the img in this post for an example, or see the docs.
To setup your openid to email link, simply login and pick which email to associate with. Done.
Suggestions are always welcome.