Help! Disk usage utility

[volocyk at skcla.monsanto.com]

Help!  Does anyone have a fast utility that reports disk usage from root
down on a per user basis?  An inode based utility would be desirable.

I'm also looking for more information on the format of the file system files.
If I'm forced to write my own utility, I need more information on how the
inode table is structured so that I can read through it.

Dan Volocyk
Searle Labs