Ran into an interesting problem on a 10.1.5 version of OSX. There is not a pressing reson to upgrade to 10.2 (yet). This particular machine is an old Beige G3 used just to run a web server for a couple of users. At 3:15 in the morning there was a power outage. The machine was not attached to a UPS. 3:15AM is the magical time that NetInfo decides to dump itself to a backup copy in /var/backups/. Well not only did this power hiccup destroy the backup copy of the database, it also destroyed the original. When logging in the only selection was "OTHER...." and you were forced to run as root.
In trying to solve the problem, I discovered Westwind Computing's article on Recovering NetInfo Domains from Backup. This article provides nice instructions for booting into single user mode (using Command-S at startup) and then restoring the NetInfo database from the backup copy. To my amazement, only 70% of the backup file was there. So now I had two copies of the NetInfo database without a good one.
Really not wanting to reinstall since I had Fink installed with a lot of packages, I decided to look at the NetInfo dump from another 10.1-based machine. Wallah! I was able to cut and paste the missing parts of the NetINFO dump file from the non-corrupted one to the corrupted one. Went through the process once more from the above reference and the machine booted without a problem and everything was restored correctly.
From now on I dump out my netinfo database twice a day and one of them is to a different machine.
Mac OS X Hints
http://hints.macworld.com/article.php?story=20021118063654918