Carlos Alejandro says: "Check out Rich Roat of House Industries' side blog."
A raccoon shimmied up a tree in plain view of my living room windows, stuck his head in a squirrel hole and couldn't get it back out. I made a butt shelf because he was just hangin' there twisting and turning and I needed to think about how to get him free without getting rabies or something. Next morning I drilled holes with a spade bit, joined the holes with a reciporicating saw and then chiseled the rest off. He climbed in the the hole and I climbed down the ladder.