I am a bit of a distro junkie. I have hundreds of disks going back many
years. I usually have at least four distros installed at once, but use
one as my main distro. I am using Ubuntu 7.10 x386, but also have Fedora
Core 8 64-bit, Simply MEPIS 7 x386, Ubuntu Hardy Heron 64-bit and
Sabayon x386 all running properly. I cycle the other distros in and out
as suits my fancy. I also run them from VMs as needed. I have Compiz
Fusion running in them all with all of the eye candy and every possible
desktop installed.

Right now I am using KDE 3, but switch to Gnome for a change of scenery
every once in awhile. I have KDE 4 working, but am not big on it yet.