Here's something any DIYer should know: Rust is alive. "Once rust forms on a tool, it will keep corroding faster and faster," says Dr. Ernest Bernarducci, a vice president at WD-40. Yikes! Clearly, the best defense is keeping the stuff off your prized collection of screwdrivers and saw blades in the first place. We hunted down a few handy products that will help keep your tools corrosion-free.