Things to add for people to use as sigs

[freebase69]

Well if you are interested enough, check out Antiarc's WoW Sig Generator. You can view/download his source code to see how he did it. He is using php files to do the creation. It might now be what you are looking for exactly but it will give you an idea of how to implement something in php. I don't think you could create hack to do this but I could be wrong.