Dell sells an XPS laptop with Ubuntu Linux installed out of the box, then you have System 76 and other companies that focus on selling you Linux-only devices. I guess your main issue after that is application compatibility. I use a VM to run Visual Studio, which is the only non-Linux application I need, but I make due with Mono Develop to some extent.
Running a VM means I get the best of both Linux and Windows. I also get the worst of both Linux and Windows. I don't think OSX has gotten bad enough for me to go that route and be forced to manage two operating systems.
