All Chromebooks and Chrometops are already Linux laptops. You can install Crouton (easy chroot) and have an Ubuntu or whatever your favorite distro is in <15 minutes.
Unfortunately I couldn't get crouton to work on a chromebook I bought recently; after switching into a chroot the screen would freeze. I think the issue might be that my chromebook has an AMD APU and an older kernel.
Recommending Developer Mode is never a good idea.