Mac users have the Macbook Air that ultra thin and light but still features a large computer screen and a full size keyboard. Forbes suggests some possible alternatives to Macbook Air on Windows:
HP Voodoo Envy 133 is priced at ~$2.1k and is thinner than the MacBook Air. Dell M1330 is a pound heavier than Macbook Air but cheaper by $800.
Lenovo Thinkpad X300 is lighter than Macbook Air and may be perfect for business travellers. The last option is Sony VGN-TZ2000 – expensive but ultra-light.