I recently switched to using KDE 4, and I don't like that KDE uses so many of the Ctrl-Fn shortcut keys, since I use them for other purposes. Specifically, I'd like to disable the Ctrl-F4 shortcut in KDE. However, I have not been able to find this shortcut in System Settings -> Shortcuts and Gestures.
UPDATE: Another shortcut I'd like to redefine is the "Show window menu" shortcut, which I like on Alt-Space, but which KDE has on Alt-F3.
I have not been able to find a global place to change all shortcuts.