Krux from Syn Shop in Las Vegas was showing off his awesome hard drive platter launcher at 2017 Bay Area Maker Faire.
It uses a microwave oven transformer to charge a capacitor bank. When discharged across a coil of wire a large magnetic field is generated which spontaneously repels that aluminum platter, launching it skyward.
Read the article:
http://hackaday.com/?p=258192
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