I'd be much more excited if you could have a single base station (that perhaps could be battery powered and GSM-capable if that was the neatest feature to peopl

I'd be much more excited if you could have a single base station (that perhaps could be battery powered and GSM-capable if that was the neatest feature to people), and then non-powered (or rather, push-powered) wireless buttons which talk to the base station. Largely the same effect, but you never have to worry about dead batteries in the buttons. I suppose you wouldn't be able to have the light on the button without a more traditional power source.