Ok. HUGE UPDATE. As my knowledge of PHP and the php GD library expands I am constantly working on new projects. I now own the domain RuneTools.com And it is fairly basic but only 3 days in the works. I spent a massive amount of time writing a script to socket the runescape server and get highscores. it then opens up a picture and the runescape font and writes a new picture.
http://www.runetools.com/signatures.html if you want to try it out. My brother and I have designed everything and would love suggestions. Also I am not the best GFX designer and I want to expand to support other backdrops. If anyone is interested in giving me the files you will be credited on the site for eternity.
I'll tell you this is funny though. I actually do not host the images. No-one does. It is generated every-time it is loaded by an error document that retrieves the url information. That has to be one of the coolest things I've ever done. These sigs don't actually exist =p
I don't recommend posting your examples though as the masking feature is not up yet.