The real power of open source visually outlined
Q: What's the point of this, you ask?
A: Absolutely Nothing
Q: How does this work...what's the general idea?
A: It's not that complicated, and there aren't really any specific rules (other than keep it clean, keep it civil, and in somewhat good taste) - and the general idea is to essentially, add on to avatar so that it evolves to perfection. You can add a new image; however, try to keep with the evolving nature and take what's currently there (avatar/image) and tweak it with your idea of creativity. GIMP, PHOTOSHOP, Whatever.
Have fun!