Well, I got bored today so I decided to make myself a sig as well.
This one uses a bunch of PHP classes I wrote to handle the GD drawing functions in PHP, as well as Truetype fonts. (GD is an image engine that's commonly used with PHP. ZZJ uses it as well)
Everything you see in my sig (except for the white text at the bottom) is being rendered by my PHP drawing, color, and font classes.
It randomly selects fonts, colors, and an OP2 image. (There are 15 OP2 images at the moment).
And if you want to see your OP2 image on it: talk to me. I'll need a 300x200 PNG file from you, which will be used as the basis of the background.
Also, if you have any Truetype (TTF) fonts that you think would be really cool, send them to me and I'll add them into the random rotation. (Currently it has 7 fonts to pick from)
Then, of course, the song information is sent to the site from Winamp... Sorry, I don't accept suggestions on songs
Only other thing I really have in mind for it is to use GIF for the final image format (so it's only about 35 k rather than 150 k). However, GD's GIF dithering algorithm sucks, I might write a PHP implementation of the Floyd-Steinberg algorithm to handle that better.