Got some old tires in the garage? Don't think of them as eyesores. Those are handy wood-splitting devices that can save you time and trips to the chiropractor. Stack spare tires on top of or around a chopping block, and those worn-out Goodyears will hold wood rounds in place while you work ax magic. The wood stays inside the tire, so you can split smaller and smaller pieces without having to bend over and pick them up each time the ax falls. When the wood splits cleanly, the tire helps keep your ax from biting deeply into the block. Miss the round entirely--hey, it happens--and the tire catches the errant edge and guards your legs against a horrific gash. Here's how it's done.