This mouse will be available in March. Looks real slick, and it does address all the issues I have with carrying a mouse and a laptop.
Bluetooth stuff costs too much (this is $70, which is close to the realm of possibility). It stores inside your laptop (cool), recharges while stored (nice, no batteries to replace), and just seems cool.
The only downside I can see so far is a lack of a scroll-wheel. None of the reviews I've seen have mentioned that capability, but I'd definitely miss that if it's not available.