Looks like an intersting approach to IP telephony. Of course, if they run like Packet8 and then go out of business you're in trouble. I'd consider moving my Vonage over to this and just leaving it plugged in to my server in the closet.

If you don't have a computer that you leave on then this is a bad idea. If you have a small handset that you travel with and would rather use that than a softphone this isn't a terrible idea, though I can't imagine traveling with a handset.

Nifty technology though.