Perfect use for an old hard drive, a grinder! via Hackaday.
More:
HOW TO – Making a hard drive laser oscilloscope.
HOW TO – Build a 15000 rpm Tesla Turbine using hard drives …
HOW TO – Make hard drive speakers.
Hard drive art…
Old hard drive orchestra.
Make – Volume 12 – $1000 Wind Chimes (DIY: Home) (Page 133).
hard drive grinder = bad idea