The Enlightenment window manager is a completely configurable window manager for X windows. You can change practically everything about it. Don't like the buttons, change 'em. Don't like the window borders, change 'em. Don't like the menu options, change 'em. etc. There are a lot of pre-made themes out already. You can have enlightenment look like a Mac or BeOS, to the craziest eye candy in existiance. Check it out, it's cool!
Enlightenment is written mainly by Carsten Haitzler, aka Rasterman. You can get find out how to get Enlightenment at the Enlightenment homepage. You can get themes at e.themes.org.
I'm currently runing E DR0.15.4. Installed from RPM.
Current problem: No sound. Install enlightenment from source?