A wonderful tip about a hack was send to me yesterday by Joe. It describes how to change the way a PC, or most other devices that use a power source, can be protected by by a simple magnet and some stuff that does not cost more than $5. All you need is a reed switch, a magnet and some duct tape. It does secure your pc as well from someone that wants to turn it on without your permission.
You basically cut the power button cable of the motherboard, install the reed switch (controlled by magnetic fields) in between and tape the reed switch to the front panel. Now, whenever someone presses the power button nothing happens. Only if you press the magnet against the case at the position where you placed the reed switch and the power button the PC will turn on.
This is of course a basic protection and someone who really wanted to access it could simply remove the switch again or replace the power unit in the PC. Take a look at the video below that walks you through the installation of the protection.
It is obviously also possible to simply take out the PC's hard drives to connect them to another device to load them up. You can counter that with encryption though, with programs like True Crypt being very effective in this regard as you can use them to encrypt the full disk.
Update: The video is not available anymore unfortunately and we have removed the embed code from this article.
Update 2: The video has been posted to YouTube where it is available again. Below you find it again embedded.
It requires at least some knowledge of electronics and how PCs works, and is not recommended for people who never hacked their PC before.
Ghacks is a technology news blog that was founded in 2005 by Martin Brinkmann. It has since then become one of the most popular tech news sites on the Internet with five authors and regular contributions from freelance writers.