AppleJack for OS X
This nifty little app just got installed on my PowerBook for extra peace of mind as I’m traveling next week. It’s a rescue utility designed for single-user mode. A couple of its functions are simple wrappers for fsck and diskutil repairPermissions; but it also can clean up cache and virtual memory files, and check the integrity of preference files. Read the reports from MacFixIt and xlr8yourmac for more info if you’re curious.