Crouton[0] is one option for that, but I would recommend GalliumOS[1] to anyone interested in a Chromebook. My current laptop is an Acer C720, purchased for $110 and running GalliumOS. It's not shiny or new, but it gets the job done, and it's practically cheap enough to be disposable. There are admittedly times when I wish I could justify the cost of a Pixel or an XPS 13, but I can't really get past the idea of being able to buy a half-dozen other machines for the same price.

[0] https://github.com/dnschneid/crouton [1] http://galliumos.org/