Seuss said:

The only truely secure way to erase a hard drive is to destroy the platters, turning them into scrap metal.

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So to accomplish this in a timely manure you would need to set up the following. 

Take 4 grams of thermite http://www.thecatalyst.org/other/thermite/

Place in a plastic baggie with an Estes model rocket igniter. http://www.rocketfun.com/listings/main_engign.html

Attach wires to a dpst switch (Radio Shack) attached to the front of the case. Along with 12v dc source of power (That would be the red wire on any of the computer power supply plugs) Tape baggie to the top of the hard drive.

Place fire extinguisher in same room (this is just in case)

In an "emergency" you flip the switch and poof no more hard drive.

(From experience) When the switch is thrown it quickly burns through the hard drive, the floppy under the hard drive, the bottom of the case, into the wooden desk and starts a small fire. 

Foot note. Buy the switch with a protective cover. Just so you do not accidentally hit it with your beer. 

Quote:

You could get rid of all of your data by formatting it then filling it to the brim with pr0n. All the 1's and 0's are taken care of that way.

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