I’ve just updated HFSDebug for Mac OS X 10.4 “Tiger”.
I think this is a pretty exciting update, even for something as unexciting as a “debugger”. The following primary changes have happened:

hfsdebug now understands and displays the on-disk raw structures corresponding to HFS Plus extended attributes.
In particular, hfsdebug can process Access Control Lists (ACLs) from scratch, [...]

The result page for the Mac OS X Expert Challenge is live.
Result and Report: The Mac OS X Expert Challenge 2005.1

The challenge encompasses two partially overlapping areas of expertise:

Operating System Internals
Security

My goals for this endeavor are the following:

Probe popular interest in system-level Mac OS X topics. Knowledge of such interest is currently valuable to me as I am creating a book on such topics.
Gauge the inquisitiveness and initiative of the Mac OS X community based [...]