Using Avatars on a wordpress site and letting the user choose their desired avatar

Hi,

A client wants to use an avatar system on their wordpress site. They want to allow the user to pick a specific avatar when the login to the members only area. Then the system remembers this and they keep that avatar each time they use the site. ARe there any plugins/systems that can do this?

You can see an example of an avatar being used on this site:

http://www.aficreditsolutions.com