Right-Alt + Print Screen + k
I haven't tried that in fedora but it works in ubuntu...
--- or ---
1. In the menu, go to System->Preferences->Keyboard (not Keyboard Shortcuts)
2. Go to Layouts tab, click Layout options
3. Expand “Key sequence to kill the X server”. Check “Ctrl+Alt+Backspace”
Last edited by ionrivera; 10-06-2010 at 10:24 PM.