1. Looking at real estate - I can record a location for any interesting properties I look at, which is useful. I have used it to measure whether the property I am looking at is really the one on the cadastral maps, as well as to confirm property boundaries. Yes, it is that accurate. Mine is as good as +/- 8m accuracy. Newer models are even better.
2. Canoeing - I can record a track and any interesting points like rapids & their grade as I go down a river.
3. Mountain biking - I can record my route, interesting points, elevations, speeds, as I travel around
4. Driving or 4WD'ing - This is another good use, though you need to make sure the device is near a window. Newer devices have even better satellite reception. I have used my device on trains, cars, bikes, in all types of topography. They can struggle a little in steep river gorges on overcast days, particularly when you are moving at 100kmph. They struggle in Japan on trains if you are going through a lot of tunnels in mountain areas. but otherwise they are great. The last problem is the need to ensure you recharge your batteries, otherwise you could be up Shit Creek and not know where in your rectum you are exactly. Its good to know!
5. Mountain climbing - This is another application so you can use it to get back to base on a different route if you like.
More generally they are move flexible than maps because they give you what you need. Maps give more info, but are less manageable, folding out a big sheet. There is a role for both, but a GPS is more compact and flexible if you get one with a high memory capacity, and good waterproofing in rain or river swamping.
The big benefit is the fact that satellite use and software is free. Once you pay for the device (say $200-300) for the better Garmin devices you can get free (easy to use software) from EasyGPS and there is no need to sign up for satellite use. Bear in mind the satellites used for GPS devices are different from those pseudo-GPS capabilities you can get on some cell phones. They are using the triangulation capabilities of the phone to locate you using cell phone towers. That is great and accurate for city locations. Just there are 2 problems with that. In most countries you will pay high download charges, so you will likely not use it unless you are pissed or too needy for some companionship from friends. I can see this being useful in Tokyo looking for some small bar in the middle of nowhere, but in Sydney going to the regular...no benefit. The other problem is its not really a global solution. You will likely find you can't get the service so readily overseas, and you will pay. The other problem is that its a city-only function, and for the large part its a capability you want in the countryside I think. I can use my satellite GPS in any country without restriction. I love it. Its a guys toy.
I was using Garmin's Waypoint Manager before. The problem was my software is in Japan, so stuck in Australia not being able to download the software, going back to the Philippines soon for another trip around the Philippines, and I need a solution. The solution is EasyGPS, free to download off the internet any time. Cool!
Andrew Sheldon www.sheldonthinks.com