I showed my wife that certain types of drill bits are unlikely to pierce the skin unless there's quite a bit of pressure pushing it by attempting to drill into the palm of my hand.. That convinced her that it would be okay to allow our 4 year old (at the time) to use an electric drill. (in addition to the electric jig saw... likely to do no more harm than pinch his fingers - he was building bird houses.) He's 16 now, and can effectively use more tools than 80-90% of the adult population... I freaked out the day he completely tore down his dirtbike, just to wash every piece. A little later, it was back together, without a single leftover part. And, like a typical kid, half my tools were still laying in the driveway as he drove around the track on his bike.
