When I travel, I take my handheld GPS and store waypoints at important locations. I have waypoints across Turkey and France. Although the GPS is ostensibly intended for sailboat navigation, I think of it as a geographic diary. In it's little memory are the places I've taken it. I can tell you, in a matter of seconds, exactlly how far it is from where I'm sitting now to Marmaris on the south west coast of Turkey, or to Angers, a small town in western France. Or the exact spot where my snowshoes didn't support me in the fine powder and I sank up to my waist in the snow near Quebec City.
Now that's inherently cool.
However, no matter how much adjusting I do to the thing, the altitude function never seems to be right. I'll be standing on a 1000 foot hilltop and it will tell me I'm at 200 feet. I'll be sailing in Long Island Sound and it will say I'm soaring through the clouds. Sailing along in a friendly breeze can feel like flying, but I don't think the GPS is capable of presenting interpretive data.
So no matter how magical I think my little GPS is, no matter how much fascinating data it can provide, I have to put it down and look around me to see the view from sea level...