I have a two year old Gazelle Professional from System76. Everything worked out of the box, and in the one case I had an issue (related to reinstalling the OS from a thumb drive), the System76 tech support was absolutely fantastic. Got a direct line to someone who knew all about Linux internals and was able to fix my problem before I could finish articulating it. And for less than the price of a Macbook Pro, I got an i7 processor, two hard drives (Ubuntu preinstalled on a 128GB SSD + a 500GB HD for storage), a beautiful 1080p matte screen, a nice graphics card, and 16GB of RAM. Like I said, this was two years ago and it's still better than most laptops you can get in the price range. The only downside is that the thing is like 6 pounds and sucks up power, but as desktop replacements go I think it would be hard to find better. So the options are there, just not in retail stores yet.

Unfortunately, they seem to have cut the price and removed the discrete graphics card option from the current Gazelle Professional. I guess that makes sense given the state of Linux gaming, but being able to run CUDA on a $1200 laptop was pretty awesome :(