Comment Ultrasonics (Score 4, Interesting) 25
"Ultrasound waves" is incorrect usage (source = http://en.wikipedia.org/wiki/Ultrasound_(disambiguation) ). Starting with "ultrasonics" or "ultrasonic waves" would have been more apt.
I love that slashdot is pushing articles on ultrasonics. Ultrasonics seems like the field of the future to me. I remember my first encounter with ultrasonics in gradeschool. I had a friend that broke his arm skateboarding]. His doctor prescribed an ultrasonic bone massager that was intended to increase the rate of bone growth (he had a cast as well, the doctor was not some new-age psuedoscientist). Fast forward into college, when I was interning at a consumer goods manufacturer. They used ultrasonics to bond together nonwovens! Totally sweet. The process used a very specifically shaped piece of metal, called a horn, which flexed in a very specific manner when subjected to ultrasonic frequencies (ultrasonic transducers can perform this electric to mechanical energy conversion). It requires a whole lot less energy than what was done before, which was more like hammering nails - you have to smash super hard, and the whole ordeal is more of an art than a science). Nowawdays they are beginning to use ultrasonic waves to benefit the flow of polymers in injection molding. Oh yah, and like you already mentioned, magnetic storage. This field is just skyrocketing.