The fascinating world of gyroscopes

Gyroscopes are fascinating things to watch moving, as well as on pictures. Precession is one of the reasons of how gyroscopes work, and its strange behavior can be easily understood in pictures. Gyroscopes are the heart of practical inventions like artificial horizons on planes, boats and spaceships, even the Segway transporter. They can be found also on not-so-popular inventions like the 40's Gyrobus. The amazing Levitron [YouTube video] is a well known gyroscopic magnetic toy that can do really weird tricks. A British inventor and engineer, Eric Laithwaite, was really fascinated with gyroscopes, as one of his lectures for children, Gyroscopes: The Engineer Through the Looking Glass shows. He's the guy that invented the linear motor and the maglev train. But after suggesting that the Laws of Newton could be wrong or maybe not valid for gyroscopic things, an outrageous heresy at the time, he lost all of his credibility. Lots of people worked on the chimera of gyroscopic propulsion since then, based on his ideas. He ultimately filed and obtained a patent for a reaction-less propulsion system [PDF] but, as could be expected, there are no working models yet, for a good number of scientific reasons.