Here’s a guide for recovering protection passwords from ATA hard drives (translated). These passwords are stored in a special area of the hard disk that also contains the firmware for the device. Normally you can’t get at them but [Supersonic] walks us through a method used to grab the data off of a Western Digital Scorpio drive. Booting into a program called MHDD you are able to bypass the BIOS (which won’t allow you to read protected data) and directly drive the SATA or PATA controller on your motherboard. Once you’ve dumped the data it can be viewed with a HEX editor, and if you know where to look you can grab the passwords that are locking the disk.
This reminds us of some of the original Xbox hacks which used a variety of methods to unlock the stock hard disk.