Here's what I've done to xp so far:
Changed the system font to superazor (trying to imitate the Wipeout game font)
Hacked it to use unsigned themes
Changed the cursor and audio sounds to the Vista versions
Changed the system icons using IconPackager
Removed the start bar using ObjectDock
Added shadows to the windows using yzShadow
Added ability for transparency using glass2k
And a few registry edits to remove all the clutter from the desktop and start menu (recycle bin was removed for example)
A few tweaks to the program interfaces and some cool backgrounds/themes and this is what you get:
http://img522.imageshack.us/my.php?image=screenshot3fb2.png http://img522.imageshack.us/my.php?image=screenshot2il8.png http://img514.imageshack.us/my.php?image=screenshot1mb3.pngNotice the program I'm working on.
It's a graphical interface sprite/pic/map editor. With it you can freely edit 8x8/16x16 in B&W/Grayscale in any combination with a push of a button.