David Schneider's excellent script to install complete GNU/Linux environment(s) as chroot(s) inside Chrome OS (or Chromium OS) with "developer mode" enabled. Supported distros include: Debian, Kali & Ubuntu
Grml is a bootable live system (Live-CD) based on Debian. Grml includes a collection of GNU/Linux software especially for system administrators and users of texttools. Grml provides automatic hardware detection. You can use Grml (for example) as a rescue system, for analyzing systems/networks or as a working environment. It is not necessary to install anything to a harddisk; you don't even need a harddisk to run it.