Even though I use an ultrabook for several months, I saw it from inside only recently.
(Yes, you understood correctly. This is the XXI century, and a remote access is available for both the ultrabook and an ordinary computer).
Thereafter, I was not interested in the technical specifications of ultrabook, but I wondered about its physical parameters, and they did not disappoint me. Ultrabook was really slim. It could be even hidden under a sheet of paper.
Its weight has exceeded all expectations. Yes, the ultrabook is light, but it is not ultra light. My Asus Zenbook UX31E (as well as other models, including the Lenovo IdeaPad U300s and Dell XPS 13) weights 2.8 puonds.
To be more precise it weighed before. We were able to reduce its weight by almost 1.1 pounds!