I'd just like to report that after updating the steam version to .21 today, the crashing issue I had when trying to click on settings or start a new game is now fixed. I don't know if it was fixed as a bug or if this was a side effect. At any rate, I'm ecstatic that I can finally run it on my linux laptop. As far the slowness reported by the previous poster, I do notice some slowdown on Kerbin as well, but for me it isn't as bad. I'm using 64 bit with the open source AMD graphics drivers.