Understanding the point that most EDC's can't afford the space a GPS takes, I personally see a GPS (and the knowledge to use it) as required gear if someone is going off the "familiar" path. A properly used GPS and compass can quickly resolve many, if not most, "lost" scenarios.

Thinking about the guy wandering around the lava field ... the root cause was that he coudn't find his way back to his vehicle, though clearly he was ill-equipped for an overnight stay (I'm thinking mostly water here) and didn't follow many safety rules. If he knew how to use a GPS and had created a waypoint for his vehicle and had used a compass to follow a bearing taken from the GPS, he would have been much much more likely to find his vehicle - though I can imagine it would have been very hard to spot his vehicle in the dark.

I once got terribly lost in downtown Taipai, Taiwan. It was late at night. I was suffering from jet lag. All the streets and signs looked the same to me. It was very frightening. I managed to find someone who spoke English and they helped me find my hotel.

Since that time I don't travel to an unfamiliar location without my GPS and a decent compass. I learned my lesson. Whether going to Palm Springs, Yellowstone, or the Nicolet forest in Wisconsin, I bring my GPS and compass and create a "home" waypoint knowing that I can at least always find my way back "home".

By the way, I find following a bearing in a city much tricker than in the country since you simply cannot walk a straight bearing - you can't walk through city blocks.

My preference is a relatively simple small GPS. My choice at this time would be the Garmin Geko 201, though I've had a Garmin GPS III+ for many years. All it has to do is store a number of waypoints, tell me where I am (in UTM coordinates), and provide a bearing and distance from where I currently am to a selected waypoint. Another feature that I find critical is the ability to connect to a PC so that I can download/upload waypoints stored on my PC using ExpertGPS software. I try to download key waypoints before leaving for a destination.

Also, I find trying to follow a bearing using a GPS only to be very frustrating. The only decent way to follow a GPS bearing is to use a good compass.

All that said, of course I also carry short-term survival gear to help me meet whatever immediate needs arrise. If the GPS and compass doesn't get me out of the situation quickly, the plan is to park it and wait for help to arrive while handing needs (health, water, shelter, signaling) as appropriate. Sometimes I bring more gear, sometimes less, depending on where I'm going.