I saw Bowie play it a couple of years back and was totally captivated. Asmall analog stylus-operated keyboard with a single oscillator which is controlled by a metal plate with 20 keys printed directly on the synth electronic board, the keys are played with the stylus. it's got three different organ sounds plus an optional vibrato mode which sounds like a spooky haunted house and is deadly for some drone behind tracks. It's got a tuning knob allows you to tune it or do pitch-bending effects which sound mad. Headphone jack output and a built-in speaker with volume control and an audio input to mix your music with the synth and have them both coming out together from the speaker! Not expensive and endless amount of groovy electronic fun
I have three of these which I received at one time or another for birthdays or christmas. I say it's a gimmick or a toy as I don't think they sound that good personally and they are not very responsive.
They have three inbuilt sounds and you can get soem interesting sound when ran through additional processing, like stomp boxes or effects units