some times ago I've tried to configure my wiimote to work in MS windows, just to use it as a light gun with mame. I've desisted after a few hours because of the lack of a software that could detect the wiimote like a plug'n play device (glovepie was too long to configure for my taste), the inaccuracy of the pointer (using glovepie) and last but not least, the absence of a "real" light gun shape, wiimote.
Well, now I've found a user friendly software that detect my wiimote "on the fly" and seems enough accurate (using sensor bar) in desktop use, at about 1,5 -2 meters discance from the monitor (you can find it at this url
http://forums.whirlpool.net.au/forum-replies.cfm?t=1192317).
I've also found a really badass (machine) gun with wiimote and nunchuk integrated...

... There's only one problem: the wiimote is not recognized by mame (probably because of the raw imput detection method used by the emulator)...
So I'm here to ask your help to solve the problem; any suggestion will be appreciated
----------------UPDATE---------------
I've tried it with an old version of mame that supports direct input and it works (quite) well: the pointing accuracy is not bad... the "feel" It's almost the same as using wiimote with a real wii to play on rail games.
Unfortunatly, wiimote buttons are not recognized by MAME; so, the controller works only as a pointing device.