If you're a big fan of abstract art and you also happen to like Windows Vista then this Pocket PC theme should be right up your street.
The psychedelic WinArt Theme features a heavily morphed, swirly version of the colorful Vista logo, standing in front of a black background. It makes for a striking central image and one that's a lot more stylish than your average wallpaper.
WinArt Theme also transforms some of the menu colors to a rich, dark blue color, and it also tweaks the Start menu transparency a bit.
It's perhaps not immediately obvious that this is a Windows logo, but WinArt Theme is still an attractive skin.