Your probably using a nice Redhat/Mandrake etc? If so, you might want to try a fun challenging install of Slackware or the unique freshness of GoboLinux. BSD is always fun, and there's a lot of new alternative OSes popping up like AtheOS, OpenBeOS (and the various other BeOS implementations) etc if your looking for an adventure. If you want to have some fun inside of your current distro you could try different windowing systems than X11 like
Fresco,
PicoGUI, or
DirectFB. I haven't read or researched much about PicoGUI, but Fresco and DirectFB both support translucent windows, Fresco is a very modern windowing system with window rotation and scaling and fun stuff, and DirectFB is a very lightweight system using Linux's builtin Framebuffer system (provided that there is a Framebuffer driver available for your card). With Framebuffer I believe most of the drivers are hardware accelerated (all of them by nature? idk).
PicoGUI is a very all in one system, window manager, toolkit and all is straight in the window server.
If you want a good sized list of other OSes just go to fuckmicrosoft.com's homepage. You might want to try other Desktop environments (not just KDE and GNOME) there are a great many window managers and desktops out there, none as popular as KDE/GNOME but some with fun features. Hey, maybe now that you've gotten used to Linux with X11, maybe try getting used to using the console, and move off of X11 for awhile for fun. `startx' will always be there waiting for you
. I'm particularly interested in BlueEyesOS (a BeOS clone) which will be based on Linux and X11 but will be very speedy and crisp on the graphics side (unlike damn near all the other toolkits I can think of). There are so many things you can do in the world of open source, only your time and hard drive space is the limit!
