Gravatars are the universal avatar syndicated over the web.

Super easy.  From  “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?”

There’s even a video on how to set it up and how and when they’re used:
Sign up.  Add email address(es) that you use to comment or post to WordPress blogs.  Add a photo (or logo) that you’re going to use throughout the web.

Lather, rinse, repeat 🙂

After signing up, you can go in and manage your Gravatar images on a whim.

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