I've been tracking us on our trip using my Rhino, which is a cool FRS/GPS radio from Garmin. It's quite cool, as it allows you to broadcast your location to your friends who also have Rhinos. You then show up on a little map on the screen of the radio.
It is also working well to give my G4 laptop a GPS fix so the program TOPO can show us exactly where we are on a nice topo map (which have almost no use for driving and are really meant for mountaineering).
When i was in Hong Kong, I picked up a cheapo USB to Serial Port adapter that looks like a little dongle with USB on one side and a Serial Port on the other. It worked great on my PC laptop which i never use, but the Keyspan software for the Mac didn't recognize it. I decided to check VersionTracker to see what was available to drive it and I still had no luck, then i googled and found a company that offered a similar generic USB-Serial adapter and low-and-behold it worked great.