There are several ways to figure out what files are being accessed by a specific application in OS X, which can help when troubleshooting various settings and system features.
Sometimes a specific disk image in OS X will automatically mount if a file on it is targeted by the system. Here are some methods for fixing this issue.
Tip: Monitor disk usage in Mac OS X 10.2.x
What's eating your disk space?
Another follow-up to the Repair Permissions debate
Apple issues Security Update 2004-4-05
Apple posts Security Update 2004-05-03
Troubleshooting Mac OS X 10.3: Network