I've just been looking into this and...How long is a piece of string :-). Both the Palm and iPaq would be suitable replacements, or any of the variants that run Palm OS or Pocket PC OS (or sybian although that is less common). One thing I found is that *no* GPS manufacturers allow you to download other peoples maps to the GPS. They only allow you to download maps from their own range. However, there are several good mapping products that run on Palm OS and Pocket PC that allow you to up/download waypoints, routes and tracks to and from the GPS and to and from a PC, most if not all of these work with Garmin and Magellan GPS's. This means you can scan and calibrate a map on the PC, dowload it to the PDA, plot your route etc on the PC or the PDA and download it from there to the GPS. These products also allow you to use the PDA as a real time scrolling map. This is the kind of system I want but I'm waiting until a handheld GPS comes out with bluetooth so it's wireless. If you want to do this kind of thing then get a PDA that takes memory cards like compact flash or SD, this is so you can basically have unlimited memeory and store lots of maps without carrying a PC around ;-) If you get one that accepts compact flash type II, it will also take an IBM microdrive which is a tiny hard disk and gives you 1Gb for about 200UKP.