Dell have announced that their linux based XPS13 ultrabook (codenamed "Sputnik") that was launched in the US last November is being updated and launched in Europe. It's a powerful spec, probably intended for developers - but it could be ideal for Lightworks
The ultrabook is a joint project from Dell and Canonical, makers of the Ubuntu distribution of linux, and comes with Ubuntu 12 preloaded.
When it was originally launched in November it only had a 1366 x 768 display, which received some criticism, but "Sputnik 2" has a 1920 x 1080 Full HD screen.
The system has a third-generation Intel Core i7 processor with Intel HD 4000 graphics, 8GB of RAM, and a 256GB SSD. It weighs just 3 pounds (1.4kg). Price in the US is $1549
Although targeted at developers this should make a nice little portable machine for editors running the Linux version of Lightworks :-)
Full details on Dells US site here