N800, Holux GPSlim 240, Maemo Mapper. 16GB SD card. This combination works great for my needs.

The Holux receiver is based on the SiRF Star III chip. The unit is very small (64x22x15 mm). It runs a long time on a charge. The web site says 8 hours, but I wouldn't know because I leave it plugged in to a 12V receptacle in the car. My lock-in times are generally within 30 seconds. Of course, this is a function of the receiver, the environment and the current configuration of the GPS satellite array.

I use my system to track my location while driving cross country using downloaded road maps and satellite maps. I don't want or need turn-by-turn directions, as one might while negotiating freeways in an unfamiliar metropolitan area. I recently downloaded maps for a 3000 mile trip around the US Pacific northwest, and the system worked flawlessly. The large capacity SD card provides ample storage space for maps.

I wouldn't say Maemo Mapper is the easiest to use. It has lots of capabilities and if one studies the help pages he can learn how to do what he wants to do. From then on, it is quite easy to use.

I have the Holux M1200, really really nice.

Wintec G-Rays1

http://www.buygpsnow.com/wintec-g-ra...mount-834.aspx

N800 and N810.

Up to 10Hz, 5Hz with WAAS, gblox based. More than adequate size and battery life.
WAAS satellites need to be set manually.

I use the Qstartz Platinum 1000 which works excellently with any GPS app on the N810. In many cases it has a fix indoors in non-concrete buildings.

I used a Holux GPSlim 236 with my N800 and continue to use it now and then to supplement the ***-GPS on my N810.

It's been great, 15+ hours of battery life, a slot for an antenna (if you're into that), and a very quick time to fix.

RoyalTek RBT device, but branded as wayfinder. Has the SIRF 3 chips. Uses same battery as Nokia 6300 phone. No complaints.
http://www.wayfinder.com/?id=913&lang=en-UK

N800, OS2008.

F-Tech solar mini bluetooth GPS. Works great, long battery life with the solar panel built in. The solar panel is too small to completely keep up with the power demand of the GPS, but it will last ~30 hours. It has worked with every device I've tried it with, including my N800 and several Palms, and my Eee PC. Bluetooth GPS receivers are pretty standard, and they should all connect easily. Newer chipsets will get better reception and quicker locks.