IFS DASD space analysis tools

What do you all use for reporting utilization of IFS (I mean stream file
systems, non-QSYS.LIB) space?

Since starting a bunch of java development, space is being used like crazy
and I don't have any good tools to find out where and by who. I am looking
for something like the DISKTASKS menu Library report, only working on
directories. It would be nice if it would ask me where to start and how many
layers deep to go, and then give me a total byte count for all the files
under each directory branch. I am looking for more of a batch reporting tool
that I can run periodically rather than a real-time monitor.

I'd hate to buy something because it doesn't sound that hard to write - I
just don't have time right now.

I have searched the archives bit haven't had much luck finding what I am
looking for.

I thought there were some PTFs issued a while back that added some IFS
management commands (or I might have dreamt that).

Thanks,
-Marty