I just stumbled across the Gorrillapod from Joby. Basically, it's an uber-flexible tripod, that doesn't need a flat surface (or, in fact, any surface) to work on.

You can set it up on an uneven patch of ground, and just bend the legs into the shape you need. If you can find a nearby Pole, or tree,you can wrap the legs around to get a stable platform to shoot from.

Excellent technology. It's on my wishlist.