I bought a $250 chromebook and a new SSD just to run Ubuntu as my daily driver and it's been great! Of course I've written scripts to reload network-manager on wake, add the keyboard backlight driver back into the kernel after updates, and I can't let the battery dip below 2% or everything will be erased...
I bought a Dell Chromebook 13 with an i5 processor and I upgraded the SSD. In the end, I might have been better off getting a Dell XPS 13 Developer Edition, but I am somewhat smitten with this pretty amazing little machine. I am worried about flashing the BIOS and bricking it, but that seems to be the only way, apart from constantly charging it, to avoid loss of data.
Why flash the BIOS?
I have a Dell Chromebook 13 (i5/8GB) and I upgraded the SSD to 256GB.
I installed Linux Mint 18 (Sarah) on partition 7 which I can dual-boot into and I have several crouton chroots installed to run with CrOS.
I find this a perfect setup for my needs.