I know there is wiicontrol. But now with full X and tv out I think porting this would be really awesome:

http://www.resplect.com/xwii/

Basically, instead of just buttons, you can use the "infrared sensing" to control the mouse IE point at things on the screen. A wireless sensor bar needed can be bought for $15.

A few weeks ago I did package it for my n800. It works but took 40% cpu load. cwiid and wiicontrol behave much better. See http://home.kabelfoon.nl/~neil/maemo/wii/ if you still want to try it.