Caveat Emptor: Never done one for real in a powered a/c.
That said, I'm a glider jockey as well as a ppl, and have made a few outlandings; gliding I fly something like the SLA, and probably would continue to do so outside of a controlled airfield / in a real emergency with a powered a/c. And yes, it's the vertical angle you're interested in.
The only thing I really have to add to this topic is neatly illustrated by Dan's chipmunk page:
Q. All other things being equal, in which direction is the field the longest?
A. From corner to corner....
Glider instruction also tells me if the far hedge/wall/whatever is approaching in a hurry, initiate a groundloop - it's generally a far better way of dispersing energy.. but you're very exposed in the front of a glider. It's also advised that over 'unlandable' terrain, you sideslip in onto a wingtip. Not keen on that.
However in any emergency situation, the airframe is dispensable... particularly if doing so is helpful to the survival of soul(s) contained within.