Don't let a misguided hammer blow ruin your work. Next time you're nailing up a piece of decorative molding or thin trim, protect it with a homemade shield cut from a piece of perforated Peg-Board. Start the nail with a couple of light hammer taps. Slip one of the holes in the shield over the nailhead and tap in the nail as far as possible. Then remove the shield and finish with a nailset. This technique also works for nailing down deck boards. Just be sure to bore a slightly bigger hole in the shield to fit over the larger nails.