If you didn't know that there are four not three states of matter then you might like to check out this Commentary: Plasmas from Bill Hammack's Engineering & Life Radio Program. Bill tells in laymans terms of some of the very important roles that plasmas play in our everday life. You can even listen to a commentary on plasmas using RealAudio. The URL is http://www.engineerguy.com/comm/4471.htm.