Hillhopper,
You can get software that will let you key in the lat/long readings for property corners (does not matter if there are only 3 or 4 or 20 corners) with different twist and turns as long as there are straight lines between the corners, and it will calculate the acerage and print out a plot of the land.
If you are buying land and the survey is old (say last one done in the 70's or 80's) back when they used the 100' chain pull method, well the acerage may not be very accurate at all.
Instead of paying for a survey (expensive) you can just get the lat/long readings from the corners with a GPS and enter them in the software and it will calculate the acerage within 1/100 of a acre.
If you had a large tract that you were wanting to split up and sell, you could play around with the corners on the smaller tracts until you get them all split up into 5 acre tracts (just a example).
I did not think about the GPS unit possibly doing that for you, or perhaps some software that comes with the GPS having that ability.
Could be.
The software I was looking at a couple years ago was called metsandbounds. Probably still available online if you look around.
Edit-Add - I looked around online and found a download for the metes and bounds software on cnet site.
download.cnet.com/Metes-and-Bounds/3000-2064_4-10413432.html
TNhunter