Among his favorite inventions:
How about a miniature transmitter, disguised in bird droppings. It splats against someone's window. You know how birds come along and shit on your window, it's sort of a whiteish, blackish, greyish mess and you see a little drip at the bottom? Imagine that drip is actually highly conductive silver paint. That long drip is actually the antenna, and in that gob is a very tiny transmitter with a tiny battery. A birdshit transducer was one of my favorites.(Via H.R.)