I had typed this up while flying to NYC, but forgot to post it, so here ya go!
Probably one of the coolest 'geek' things I've done in a while occurred on out flight from dallas to nyc. I got out my eeepc and hooked up my usb gps device to see if it would work. It took a while, but sure enough, we were at 34466 ft cruising along at about 554 miles an hour.
I use microsoft streets and trips, and the zoom level was set to street level, so as you might imagine, the map was having a hard time keeping up!
I zoomed out to basically state-level, and there we were, flying across pennsylvania. as I typed this up, we lost the satellite signal, but I think that's because I had the unit down on my arm rest instead of in the window. Oh, well, it was still cool for a while!