The short: want an image of yourself associated with comments you make on this blog (and many others)? Read on.
Gravatar was recently acquired by Automattic, the company that supports WordPress development and runs WordPress.com. I never bothered with it before because it was notoriously slow, but Automattic beefed things up and it’s actually usable now. So what you say?
Gravatar is a “globally recognized avatar” that lets you have a profile picture associated with your email address that can (in theory) be used on any internet site that you use your email address for. This means that when you leave a comment here, you get a little photo icon of your choice that’ll appear. The bonus is that it’ll work on any other site that supports gravatar, including every blog on WordPress.com. Even better is that anyone who blogs on WordPress.com already has their avatar there associated with gravatar.
So, if having an icon on here (and many other places!) when you comment suits your fancy, go sign up.
(And for anyone that cares, I’m using the Easy Gravatars plugin.)