My parents and I worked our butts off so I could spend 4 years of my life learning how those electrons gallop through various materials and do different things. There's a veritable playground of galloping electrons in there... Why not share the wealth? Watching them is much momre fun than watching Lemmings on your computer.
The relationship between magnets and AC current has always fascinated me. There are probably 15-30 devices that use these basic principles within 30 feet of every person who reads this post.
Clocks, speaker drivers, microphones, telephones, anything that plugs in and spins - like a hair dryer, blenders, the blower in your heating/AC system, electric pumps, the hard drive in your computer (in more than one way - to spin the platters AND to read the data), the alternator in your car...
Think about all of the things that we wouldn't have without ac voltage, wire, and magnets. It's also cool because both ends can be exactly the same. Something (air, water, steam) spins a device with a bunch of wire wrapped around it inside of a magnet. The magnetic fields "create" the power as the wire passes through them. The power is then wired to something that creates a changing magnetic field. The changing magnetic field causes something with wire wrapped around it to start spinning so that you can use it to do some kind of work. Transmitting circular motion through copper using the same components on each end...
Then you have transmitting pressure. Sound pressure waves from a singer press on a microphone pickup membrane, and it moves a tiny magnet inside of a coil of wire with some voltage running through it. The fluctuations in the "nomal" voltage travel through a wire into another coil, that moves another magnet that has another membrane attached to it that creates sound pressure waves that hit your ears and allow you to hear the singer. Pressure on one end transmitted to something that creates pressure on the other end. Again, with exactly the same components on each end (just different sizes).
Best Spock voice...
Fascinating.
Oh.. And Mark - Don't stand next to me. I'm copying off of the girl sitting in front of me. 
