A lot of websites now support Gravatars.
What exactly are Gravatars?
A gravatar, or globally recognized avatar, is quite simply an image that follows you from site to site appearing beside your name when you do things. Avatars help identify your posts on blogs and web forums, so why not on any site?
WordPress has plugins that allow you to insert them into your comments, so you have a common picture across the sites you post.
Pretty cool. I’ve got mine. How about you? :)