So what is this gravatar thingie? Gravatar is a Globally Recognized Avatar. From the gravatar site:

Your Gravatar is an image that follows you from site to site appearing beside your name when you do things like comment or post on a blog. Avatars help identify your posts on blogs and web forums, so why not on any site?

I would really appreciate it if you decided to sign up for gravatar! You can even associate one image to as many email addresses as you please. The only thing is: you need to own those email addresses. It will really make a huge difference. Please, get gravatar. Now.