Dual booting Ubuntu 13.04 on the Samsung ARM Chromebook with XFCE as my window manager. So far it's been working well as a machine to get work done when I'm away from the desktop. I rarely boot into the ChromeOS side, though.
I have the $200 Asus. I like it. I installed Ubuntu on it. I basically just use it for a portable/travel computer that I could also program on. I can easily pick it up and go skype or browse HN since I don't have an iPad.