Today Dewalt has revealed the Dewalt Flexvolt 120V 12″ cordless miter saw, the first of its kind. It runs on two 60V batteries for 120V of power. Here are a couple videos of the Dewalt Flexvolt cordless miter saw in action, cutting through a 12-inch board with no problem.
This tool can also be plugged in to run on 120V AC power, but otherwise it can run all day on the Flexvolt batteries.
Also introduced on the Flexvolt platform is a cordless table saw, and a few more game changing power tools.