PC Software and GPS recommendations

[ree]

I'm planning on mounting a small tablet PC (probably one of the newfangled origami/UMPC's) in my H2 for navigation, media, plus whatever else.

Questions:

- What is the best PC-based, GPS-enabled mapping/navigation software?

- Any recommendations for GPS hardware? The tablet/UMPC will likely only have USB2.0 peripheral ports. I think I might be able to get a PC card adapter for it, but I really want something where I can roof mount the GPS antenna and not have to run extra power to the GPS unit (too many wires).