What is the Ondes Martenot?, I hear you ask. Well, you may not be familiar with the name but if you've ever seen Ghostbusters and chances are you have then you've definately heard it being played. In fact it's the first thing which can be heard at the beginning of Ghostbusters.
http://www.youtube.com/watch?v=ll9FCC1QYhQ
This spooky, eerie sounding instrument really set the tone for the film and worked perfectly throughout Elmer Bernsteins Ghostbusters score.
The Ondes martenot is an early electonic musical instrument which was invented in 1928 by Maurice Martenot and sounds much like the theramin.
http://en.wikipedia.org/wiki/Ondes-Martenot
Below are some links to videos of the instrument being played.
http://www.youtube.com/watch?v=Yy9UBjrUjwo
http://www.youtube.com/watch?v=IA00Wug6uyc
I really love this instrument and hope to try it out one day.
I do hope that if Ghostbusters III is made, whoever composes the music for it will incorporate the Ondes Martinot into the score.