I think it was on last weeks episode. They were putting together a stair rail and to hide the screws they used internal screws with a magnetic drill. It was really cool. They had the screws placed in the two places to join the wood together. Then they put them together and used a special magnetic adpater on a screwdriver and held it up against the wood and it screwed it together! It was really something special and didn’t need any wood plugs to cover the screws at all. Really neat.