Produce eerie electronic melodies.
The theremin was the first real electronic musical instrument, and became a staple of movie soundtracks, thanks to its haunting, whining sound.
At femurdesign.com/theremin you get a taste for just how irritating it was, unless in the hands (OK, gestures) of a true master.
This is likely to appeal to people who are fond of musical history... Oh, and it will appeal to those who like to annoy everybody around them too.
**related: Play an accordion
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