Do you use a SciFi theme or other type of theme on your desktop?
Have you changed icons or fonts on your desktop?
Have you remapped any of your system sounds?

I made it multiple choice

Most of my machines are pretty boring except for some wallpaper that I use (mostly NASA type stuff).

At work it is because I develop new applications on my box so I need to see it as a typical user would.... on a stock graphics Windows XP machine.

I customize the themes of my desktop

Blackbox For Windows looks interesting...

http://www.bb4win.org/

There is just no way I could run something like that on my work machines though. :(

That blackbox stuff looks really cool. I clipped it. I may try it out. If I do I will post about it.