I use the Deadeye and Superflint system - sort of. Deadeye's method kind of creeps me out. I just lop the head off instead of skinning to the nose and plucking out the eyes.
I slit the skin across the back crosswise in front of the hips and stick the first two fingers of each hand under the skin (knuckles on either side of the backbone) and give a mighty tug. the skin rips and peels, leaving you to cut it away at the ankles, tail and neck. I just lop off all the extremities (feet, tail & head). If I'm saving the tail (Muddler flies) I yank out the bone and jamb a twig in to allow air in and hold the shape until I can get it home and poke in borax to perserve it. Sometimes the skin stays across the belly and must be slit there. Then, I open the cavity and dump the entrails. One hoh-dressed squirrel carcass.
Here's a interesting bunny system. This was in Outdoor Life a bazillion years ago (I think it must have been an April issue). Slit the FRESH killed bunny around the anus and a further 1" slit through the belly skin up from there. Then grab the bunny's front legs and swing it, from a standing position, down between your legs with all your might and snap it to a halt, banding slightly at the waist. The guts shoot out the slit, leaving a field dressed bunny, the entrails on the ground behind you and your hands clean.
Now here's the catch. You have to smack your elbows against your legs hard to get it to 'snap' suddenly enough to eviscerate the bunny. If you don't, what happens is the bunny guts string out and end up smacking you all up your back. I found this out in demonstrating it to a friend. I did it, but when he tried the results varried slightly. Luckily, his gun was unloaded and I climb trees pretty well. After that, it became a ritual to demonstrate it for someone and let him coat himself while the 'learned ones' laughed like idiots. "All there is to it. Here, now you try snicker, snicker." This works better if the 'victim' doesn't have the only vehicle, or has to ride back in yours.