SIGNATURE BACKROUND:First create new layer. Use theese options.
http://img233.echo.cx/img233/7478/g5em.jpg

Now get out a good abstract brush.
http://img23.echo.cx/img23/3775/g1kg.jpg

Now Brush it a little. You should have something like this. Dont mind the white outline thingy thats just from the brush.
http://img23.echo.cx/img23/5990/g5wl.jpg

Now press CTRL-U and use theese settings.
Hue:247 Saturation: 62 Lightness: +1. Now you should have something like this.
http://img191.echo.cx/img191/8081/g4yk.jpg

Now got o filter>render>clouds. Then go to Edit> fade clouds. Put the opacity to 50 and then change the mode to color. Now add a black border. Add your name in any text and you should have something like this.
http://img176.echo.cx/img176/1861/ik1612cd.jpg

Good tutorial , but not very unique sig itself , boring is all :P

I always do clouds before I brush in the background layer. The hue/saturation settings don't have to be that.