Found a nice little site that offers forum sigs and avatars for Warcraft, which are well put together. Check out wow.magelo.com and the examples below.
The image is grabbed by the Magelo site from the Armory, so that the image that you place in the Armory is re-used by them, and therefore by you as well. Clever.
Found via Psynister’s blog – go read it, and happy killing.