Would it be possible to pair an Xbox controller or 2 with the N900?

I don't have an Xbox myself, but can see how it could help the N900 as a gaming platform. I believe Xbox controllers can be used in PCs (Windows, but possibly Linux drivers?)

If the N900 is connected to the TV via TV out to play something like Quake or another game, using a wireless Xbox controller could be useful... sports games especially will benefit. Some games may have native Xbox controller support in Linux, so porting to Maemo would be easier (for the short term) than trying to take Hildon into account.

Would this be useful at all ? Or am I just daydreaming?

PS. I believe some people have managed to get a Wii controller to work with the N900.

Actually this would be cool and might work:

http://www.pabr.org/sixlinux/sixlinux.en.html

PS3 controller (bluetooth)

XBox does not use bluetooth, so the only way would be to somehow use the Xbox wireless usb dongle.

I guess this topic should also extend to wireless PS3 controllers, though I see PC Linux games with built-in Xbox controller support more viable, but hey, if the PS3 controller can emulate and Xbox controller, it'll be the same

PS3 pad can only sync over USB, so that is probably a none starter.
Xbox pad is not Bluetooth and so needs the USB dongle, so again its a none starter (as the N900 does not support USB in that way).

So far Wiimote is confirmed as working at least with the SNES emulator, Zeemote will probably also be supported. Other than those, its anyones guess.

And you also need to figure out how to connect it onto the N900 without bluetooth...

There are USB controllers and usb wireless receivers, and we already have usb-host beta support, so, could we try to build this on scratchbox?
http://pingus.seul.org/~grumbel/xboxdrv/
I think this could be very nice...
I don't still know if it would be necessary to compile against a specific kernel or it could be used with any one...
I have no programming skills, but somebody could try to compile it...
I will try later...