I just came by something too good not to mention about.
Subtle Patterns is a collection of *drumroll*
subtle patterns. These kind of textures are just perfect for web development. Even better there are browser plugins (for Safari and Chrome at least) that allow you to test various patterns as the background of your site.
I found this excellent site at Chris Coyier's notes. If you go through those, you'll likely pick up a few other things as well. That blog is definitely one that should go on your reading list if you are into web development.