I like the concept of the first one, but it's too hard to read. I think it looks really cool, but It took me alot of effort to figure out what it said.
Second one, the text blends in a bit too much, and the background doesn't really flow into the text, like it should because the text is the focal point.
3rd one, grainy.
Your signature is just this image off bing recolored with text over it.
http://www.bing.com/images/search?q=cool+wallpaper&qs=n&form=QBIR&pq=cool+wallpaper&sc=8-12&sp=-1&sk=#view=detail&id=8D6CC7273AA6480E4E25F8393511AAD231F575B6&selectedIndex=1