Make:

Nick sent word of his digitally squarewave take on the legendary theremin instrument - hmmm, a Squaremin perhaps?

This battery powered electronic musical instrument is a descendant of the theremin and can be played without contact from the musician. This small instrument contains two infared (IR) sensors, one controlling the note, with the other controlling the octave that is played through the speaker in the front.
There are seven possible notes (c-b) and 7 possible octaves of each note. The tone is reflected by one of seven colors that illuminates the center area and highlights a small indicator located on the top panel. The brain of this piece is a boot-loaded atmega chip.