StreetDeck is more than just GPS NAVIGATION software
StreetDeck is Microsoft Windows based software that uses the latest technology to take advantage of all the power in your UMPC, Laptop, NetBook, or other in car PC.
GPS Navigation, Music, Satellite Radio, HD Radio, and More. It makes the features you want to use in your car accessible while driving.
The Viliv x70 EX is another nice UMPC from Viliv. Like the Viliv S5, it also has a car kit and built in GPS. It is built around a larger 7" touch screen though. Stay tuned for a more in depth review later this week.

Looks like OQO will be at CES this year with a new UMPC model. Twice as fast as the old versions. I've always been impressed by the OQO form factor, but using an active touch screen (needs a pen) in the car is kinda hard. Hopefully this one will actually have a capacitive touch screen, ideal for use with StreetDeck.
Via [Engadget]