There are two avatars on this forum, the default avatar (the little boxed one, that is TW themed only) and the URL avatar.

The URL avatar has a default one, just like the normal avatar, but is able to be much bigger, and (I believe) on any topic. You can also disable viewing them, as I have. For me, they just take up too much room, the default one is ugly (IMO) and I don't want to waste my bandwith on them.

The URL avatars are an optional way to express yourself, while the normal avatars are the ones that bind us together. WE ARE LEGION.