Like someone mentioned earlier, precautionary landings have a history dating back to ancient aviation times with partial radio coverage, poor weather forecasts and party line phone communications. The Cessna checklist posted by Bentleg is preparation for a crash. Once safely down and stopped, turn everything back on and clean up.
I've had to do many strip inspections using similar techniques. Checking for water puddles, mudholes, fences, anthills, stumps, saplings, ditches, old ploughs, dead cattle in the grass, irrigation pipes, unused fenceposts and other obstructions on a patch of dirt that the squatter swore was used by large twins. (After landing you find out that the squatter was referring to the one Army Caribou that landed in the same paddock 45 years ago and was never seen or heard from again.)
Several things that I try and remember are:
1. Look out for power lines in your flight path before concentrating on the landing area.
2. Obstacles in long grass will be easy to see from overhead, but won't be seen on approach or landing.
3. Fences and loose fencing wire offcuts are hard to see.
4. Single line telephone wires on old, short wooden poles are very hard to see until you land under them.
5. Your eyes will be looking down. Be careful when you turn at the end of the run. Be aware of wind and drift, particularly if turning with the wind and still concentrating on the end of the landing area.
6. Small anthills in long grass can be a big hazard. They can't be seen until you're on the ground and still doing 40kts.