This project is obsolete. It depended on a feature of the Macintosh boot sequence which no longer exists, has not existed for some time now, and is extremely unlikely to return. Furthermore, much of the functionality that this project provided is now supplied by Apple's Time Machine utility.
Old description:
Just Imagine automates the generation of complete system disk images on OS/X or OS/X Server via a scheduled launchd reboot, running while the system disk is mounted read-only...