Can a harddrive be concidered a dangerous product? It can if you stack up all 9 platters and disable the motor's speed control! The sheer amount of energy stored in the rotation of those disks is immense. Here you can see the effects of quick rotation on such objects as dimes, CDRs, and plastic pens. Thanks much to Memblers for help on making the movies.
This is the result of a CDR meeting a small screwdriver at 10K RPMs. The coating was shed in a fine spray of reflective material.
The aftermath. Flecks of reflective shit covered the work area and the floor!
Movies of Destruction
Note to IE users; you may have to right-click and save to view these movies for some reason I haven't determined yet.
The drive spins up - It all starts with the disk spinning up.
Grinding up a pencap - The plastic pencap turned into fine strings of plastic "confetti" apparently from the friction.
A CDR bites it - A small screwdriver can be used to "blow off" the CDR's reflective coating, so long as the CDR is spinning fast enough. Notice the large piece of material that gets ejected with a bang, and the fine spray of particles.
Repelling a magnet - The rotation of the aluminum disk past the magnet induces a similar field which repels the magnet. The harder one presses the magnet into the disk, the harder the "push" from the disk is. Note this also nearly stops the disk.
Damn that magnet is strong!
Placing a dime on the disk. - Before when I did this, the dime shot out of the drive and nailed the wall good!
And finally, spindown. - The "ticking" is the regen braking trying to kick in, then when it does the disk decellerates rapidly.