Alot really, you can
- run live cds
- install any just about any OS(Linux, BSD, even Win XP/Vista/7)
- Run Utility programs and cds (hiren's, ultimate boot cd)
Sounds great, what's the catch?
- right now the package is pretty dated, so it requires a "little" configuration if you want to run more than memdisk. Hopefully it can be updated soon.
- good pxe or network booting information around the web is scattered.