I have been cutting up limbs to burn in the stove. I figured they'd at least be useful in the woodstove and put out some heat instead of burning in the slash pile. I can't seem to cut that small with my chainsaws, so I've been doing it by hand, with a pruning saw or a small (dunno what to call it, it has teeth like a crosscut) saw. It goes quickly and I can listen to the radio while cutting.
Oh, I do think I heard my dad talk about using black powder to split wood. He grew up on the wet side of our fair state where the trees were still large, as were the sturgeon.