Hint: Use 'j' and 'k' keys
to move up and down

MACLAINE

Maintaining a running collection of interesting things.

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Jerry Lewis demonstrates the Chamberlin (via MellotronMovie)

One of the earliest forms of a sample-based musical instrument.  Chamberlins have tape loops playing inside them at all times, and when you press a key, a playback head touches against the tape and plays the sound.  Very advanced stuff back then.