Like this?http://doctabu.livejournal.com/64758.html
Adding PCE console specific layer on top of that, makes for an interesting challenge (no, not a reference to Ys II).
My company already has some of these in production using a similar method. We actually used a 9-volt with it, lasts about 72+ hours. We need to sell about 500 more units to drop the price significantly, so check us out :-) http://www.wirelesssensorbar.com
This one is a little expensive. Hopefully a name brand company will release one with better battery life. I'm also hoping they can make one with better range. Optimal range is supposed to be 3-8 feet. From where I set it will be 10 feet. I'm not sure if the extra two feet will make any difference. I guess I'll find out when I get mine at Christmas.
I usually sit rather far away whenever I play my Wii, like around 10 feet or so. It doesn't work as sharply from that far away, but it's still very easy and enjoyable from that distance. The cursor will just get a little jumpy when you make close movements when you are that far away.