TOMOYO Linux is an implementation of Mandatory Access Control for Linux.
LiveCD (ISO image)
TOMOYO Linux enabled Ubuntu 7.04 LiveCD is available. It's 100% safe and fun (and free, of course) to try. Please take your time to explore the amazing world of policy auto learning.
Quick and Easy Install Guide
TOMOYO Linux on LFS
For those "tough guys", TOMOYO Linux just runs fine on LFS. Find yourself and make your own version.