Hack a computer using an iPod with Linux [via] — no matter how locked the computer is:

Firewire/i.Link is well known as a way for connecting video devices or external hard-disks to computers. One little known fact is that the Firewire protocol also allows to read and write physical memory on connected machines without further software support. This can be leveraged to escalate privileges or to spy on connected machines. Any kind of device connected via Firewire, be it hard-disk, camcorder or iPod could be perverted to steal data or insert backdoors into computers being attached to the device.

Basically, the only solution is to lock your computer into a safe, which is hardly convenient when you have an iMac (or a laptop). Interesting…