I'm a little late on this, but a product I worked on has been released by HP in their 11iv3 version of HPUX, in Feb 2007. Why did I find about it so late in the day? Well, I no longer work for HP, and I don't have many chatty, reliable sources in the company either.
Anyhoo, this was a project I joined, one that I led, one that I spent sleepless nights on, and one in which I had great fun. EMT, or Error Management Technology as it is formally called, is an online, searchable, updateable repository of error messages and associated cause/action information. It isn't very big, probably a hundred thousand lines of C++ source, and is a part of a much larger toolset called System Fault Management, or SFM, another project I contributed to.
The reason why I care about this project is that my team went through hoops trying to finish it. We had uphill struggles all the way, but we came through them, mostly successfully :), with the most harrowing experience being what we called the JOEM release - a pre-release version of the product that was supplied to Japanese OEMs. We scored a 4 on 5 for the product, and most of the objections they raised were minor, and were mostly features of the larger SFM toolset.
The joy of seeing your work in the public domain can never be sufficiently expressed in words. It is a thrill ride beyond thrill rides.
See more about EMT here. And remember, I did _not_ write the documentation.