I use this little script on another computer for a while. Meanly to remote drive my xmms throught the xmms python module. Anyway I just write this little intro here, perhaps other people may be interested..

This litte script use Xlib python module to grab keys. If the key is special key on my laptop, i use it to change the sound level. This is a short example, not a definitive app.

from Xlib.display import Display
from Xlib import X
import oss

# custom keys from my dell D400 Laptop
vol_plus  = 176
vol_moins = 174

keys = [vol_plus,vol_moins]

def changeVolume(aValue):
	mixer = oss.open_mixer()
	symbol = oss.SOUND_DEVICE_LABELS.index('Vol  ')
	left,right  = mixer.read_channel(symbol)

	avg = (left + right) / 2
	if (avg + aValue) >= 0:
		mixer.write_channel(symbol,(left + aValue,right + aValue))
	mixer.close()

def handle_event(aEvent):
	keycode = aEvent.detail
	if aEvent.type == X.KeyPress:
		if keycode == vol_moins:
			changeVolume(-2)
		elif keycode == vol_plus:
			changeVolume(+2)

def main():
	# current display
	disp = Display()
	root = disp.screen().root

	# we tell the X server we want to catch keyPress event
	root.change_attributes(event_mask = X.KeyPressMask)

	for keycode in keys:
		root.grab_key(keycode, X.AnyModifier, 1,X.GrabModeAsync, X.GrabModeAsync)

	while 1:
		event = root.display.next_event()
		handle_event(event)

if __name__ == '__main__':
	main()

As you can see, this is really trivial, and simple to hack XFree w/ python :)
I need to send special thanks to the python-Xlib author, because he does a great job, and he help me a lot the first time I hacked this.