Hooking into the input queue(?)

[Jan <jandersen informatica com>]

Is possible in X to 'listen in' on the keyboard input (assuming this is 
the right term)? I remember years back there was a 'game' called 'Monthy 
Python's complete waste of time', and the feature that my children loved 
most was the ability to make the computer, shall we put it politely, 
'play a sound' every time you pressed a key. This was in Windows 95 - it 
didn't work, really, in NT.

I know that in the earlier versions of Windows an application could hook 
in to different places in the system, among others the keyboard message 
queue, and I assume this is what the producers of this game did. How 
would one do the same in Gnome?

/jan