This posting saved my bacon today:
http://dmunsie.wordpress.com/code/hacks/
…we had an HFS+ filesystem at work that had become corrupted to the point that fsck and DiskWarrior wouldn’t fix it. The problem was that the journal had become corrupted, and fsck.hfs doesn’t know how to actually fix the journal.
I used his code to hack on the partition, disable the journal, and got the files back. Awesome.