A list of projects that I sometimes work on (or would like to):
mdchroot is “mounting debian chroot”. This is similar to debian's 'dchroot', but does CLONE_NEWNS mounts to mount directories in the chroot before doing the chroot.
Virtual Victim PC . This is a project to create a virtual victim pc that runs in qemu. Essentially, it attaches you as root to a virtual machine that you can do things as root (like test your 'rm -Rf /').