The neion theme from invaderjohn is another fine theme. It features a unique and rather cool start button along with a slick startmenu. It also includes a wallpaper in the pack. Additionally you can get the icons that are pictured.
Use on Windows Vista: Vista Ready. (see help tab if you have issues)
Use on Windows XP : Download and install Theme-Patcher (Instructions included).
Matching Icons: neion Icons