It's the Alienware X51. No doubt it will come to many as a shock, as it did to myself. It would seem Dell wants to get serious with Linux gamers, and more specifically with Ubuntu gamers. This is great news!
On closer inspection, there are several units each differing based on their hardware specs. The lowest price is at $599 and the highest [without user modification] being $1049. Now, some may say that for these prices they could build themselves a better system, and without a doubt I would agree.
However, these computer gaming systems are targeted towards the gaming consumer. Not so much towards the tinkerer and DIY enthusiasts. It's meant to be plug-and-play. I hope we will be able to see videos of these awesome machines soon (running Ubuntu of course). I'm definitely eager to purchase one *starts saving up*.
The hardware specs range from an Intel i3-3220 with a GTX 645 on the low-end, to an Intel i7-3770k with a GTX 660. Note that additional hardware can be added, and some internals can be changed which can alter the final pricing.
Currently, it would seem these units are only available to the people of the U.S.A. Hopefully this reach will be expanded, as Dell has stores in many countries (mine as well, which is Malaysia).
No doubt, this comes to us with thanks to Valve and Steam. It's even heavily mentioned on their product page, so it's relatively easy to see why they suddenly want to support Ubuntu alongside Windows.
Check out Dell's Alienware Ubuntu page here: http://alienware.com/ubuntu/