Chrome OS

Dualbooting Chrome OS and GalliumOS is possible using several methods.

chrx

(Add some information about dualbooting Chrome OS using chrx)

Careful manual configuration

(Describe how to use Ubiquity's partitioner to not destroy Chrome OS)

Chromium OS

On devices that do not support SeaBIOS on the default ROM, or dualbooting is otherwise impossible, or if you just want to take a different approach, you can download a Chromium OS build from http://chromium.arnoldthebat.co.uk/. Once you've installed it, you can run a script to convert it to Chrome OS proper. (Add more information about doing this properly)