I just picked up a Holux GM-210 USB GPS Receiver and its very small and powerful. I was able to pick up 8 sattelites in doors and 7 from sitting on my cars dash board. seems to give very stable readings and had a battery inside that remembers the last sattelite fix so on a cold startup it gets its bearings very very quick. I was impressed so you may want to pick one up too. I got mine off ebay
Got one too - ditto on the results. Im using Streets and Maps 2004, until I find something I like better. It has a PS2 connection on mine, and it came with a Ps2 to USB converter.