Any rest, any way you can get it! I have used my spotting scope tripod sans scope and padded on top with gloves or a hat, out on the tundra. Across the handlebars (with padding) of the ATV, across the snow machine windshield or across the seats works too.
The last time i used "sticks" it was on a Colorado elk hunt where I was forced to take a standing shot. I used two birch trees about a foot apart, between which I jammed my left forearm, over which I rested the rifle. 150 yards DRT with a .260.
I don't think I could have tipped them slightly toward me, however, as they were about 10 inches in diameter where I wedged my arm..
Foot-hunting, I often carry a 6' walking staff made from local birch, trimmed to about 1.25 inches in diameter top to bottom, with a padded fork on top. A monopod isn't as good as a bipod, but again I have found the steadiest position to be with the foot kicked out a bit away from me. Better yet if I can brace it, or me in some safe way against another tree etc.
