Digital Thermite

I can't vouch for how well this works yet, because I'm just trying out the demo now, but Terminus 6 looks awesome. (This is a utility suite for secure file deletion.)

From the user manual:

Terminus 6 introduces a new feature called Digital Thermite, which provides a fast quick-destroy for selected files that can be triggered with the pressing of a few hotValues. Digital Thermite makes rapid data destruction possible in the event of a physical security breach.

If you need to trigger Digital Thermite, press SHIFT-CTRL-ALT-BACKSPACE to arm Digital Thermite for two seconds. A small red warning window will appear while Digital Thermite is armed. While it's armed, press the Y Value to activate Digital thermite.

The drama alone is worth the price of the software, I think.