After my first set of batteries ran out I thought of getting 1 of these but then realised they're not available yet :(
Spotted this on Ebay:
http://cgi.ebay.co.uk/NEW-Wii-Remote...33 0078172771
It's a rechargable battery that plugs in where the batteries normally go, and connects via a wire to a USB plug (so it can charge off your Wii or a PC). Only seem to be able to get them from HK though...
In the end I just bought a quick-charger off Amazon for £15. Charges regular AA's in 15 minutes and I can use them in other stuff too
