When you reach for a tool, you had better know what you're doing, not only for your own good but for the safety of everyone around you, as well. Tools, especially power tools, are not toys. They're serious business. Like you, they work best when they're sharp. And, also like you, they aren't worth a darn when they're dull. In fact, they can be downright dangerous. A dull saw blade in a power saw could kick right out of the groove and injure you. Dull tools require the use of more pressure. A dull chisel is like cutting wood with a screwdriver; a dull drill bit can start a fire and will fast wear out your drill; a dull handsaw will twist and bind dangerously. So crack open those Yellow Pages, look under "sharpening" or "tool repair" and enlist the aid of a professional. And that's the On The House tip for today.