I do computer repair and tech support full time. Occasionally, I run across problems that are just not worth the customer paying for and I tell them so. Sometimes, when this is the case, I can convince them to give me the machine so I can spend 10 hours on it and see if I can get it working. I’m sure hobbyists of other genres accomplish similar feats.
Quite a few of the older IBM ThinkPad Notebook computers have their supervisor passwords stored on an EEPROM. The short of this is that there is no way to hack, erase, or get around the password. The only solution (as far as I can tell so far) is to recover the password by designing a crude ROM reader. One customer had a machine with this problem and I sent them home with URLs to various companies that offered to recover the supervisor password for various fees. I also sent them home with the notion that, should they be unsuccessful (or just not want to try) shipping it one of these companies, I would be happy to give it a shot just for the learning experience.
Following instructions posted here: http://sodoityourself.com/hacking-ibm-thinkpad-bios-password/, I plan on doing just that. I have lots of spare wiring lying about and actually have all the needed parts except for the zener-diodes.
I will post an update with photos when I have completed the recovery (or bricked the computer).
[UPDATE December 8, 2008]
Well I didn’t brick the computer. I built the entire circuit board and then spent an hour finding the EEPROM on the computer and then I left it sitting there with no battery over night. The next day when I went to turn it on briefly, it booted. WTF?! The password was supposed to be stuck in an EEPROM, not to mention I had already tried leaving the CMOS battery out and that had not worked.
Oh well, now I have this janky serial reader built specifically for that chip. I uploaded a few photos of the construction of the reader here: http://picasaweb.google.com/eukota/GeekAndProudOfIt#