This is a FANTASTIC add-on, allowing you to instantly create many multiple color Avatars for your different users. With the addition of the Delete all files from cache option, it makes it even easier to play around with different background & text colors.
I also wanted to state that this is the fastest-acting add-on I have ever used. I wasn't sure how long it'd take to create thousands of random colored avatars and to my surprise it was instantaneous. Wow!