Oh, and this discussion reminds me of a funny story. I work at a big marine show in New Orleans every year and a lot of the companies that have booths at the show give away pens, coozies, etc, with their logo on it. One year Sperry Marine, which is the inventor of the gyrocompass and they sell marine magnetic compasses and other navigation equipment, was giving away a small keychain magnetic compass with their name on it. Only problem is that the key ring on it was steel so no matter which way you turned it north was always pointing at the key ring.
Good idea from their marketing department, but they get a big zero on the execution.
