Australian Theremin Kits: Simple kit. The completed instrument puts out a pure sine wave tone.
PAiA Theremax: Information about theremin kit from PAiA.
Theremaniacs Theremin and Harmonic Percolators: Manufactures a pitch only Theremin with changeable timbre. Also presented is the Harmonic Percolator, a distortion pedal.
Wavefront Technologies: Makers of two models af theremins, and also a MIDI interface