I'm eying a Toshiba R700 right now. It has 13.3" screen and it weighs only 1,3 kg, but it still has Core i3, i5 or i5 CPU instead of a low power and performance CPU. Don't know about the Linux support yet, and there is a chance that it's quite noisy, but it's just come to the market, so these things are soon to be found out.