I finally found a wallpaper I really, really like. Here it is.
This is now my current wallpaper. You can download it from http://va312iremakdogan.wordpress.com/2010/11/09/helvetica/
My first runner up (all three are under the “minimalist” category) is from http://www.wallshark.com/wallpaper/nice-background-minimalism-color.html. It’s rather cute in a weird sort of way.
And finally, my second runner up. It’s from http://hdw.eweb4.com/out/389607.html.