Lenovo's ThinkPad Yoga has a keyboard that flattens when you use it in tablet mode
 

When the original Lenovo Yoga came out, everyone seemed to have the same complaint: when you flipped the screen over into tablet mode, you had to rest your hands against the keyboard on the other side. It didn't matter that the keyboard automatically disabled; it felt awkward to press your fingers into flappy keys instead of a smooth surface. Well, Lenovo seems to have taken that criticism to heart: the company just announced the ThinkPad Yoga, a 12-inch, business-friendly model with a keyboard that flattens as you flip the screen back into tablet mode. How does this so-called Lift and Lock system work? Here's the short version: as you flip the display over, a mechanical setup causes the platform between the keys to rise so that it's level with the buttons. Meanwhile, the keys get clamped in place so you can't press them. Finally, folding the screen over causes a set of feet to pop out so that there's some buffer space around the keys when you place the "tablet" face-up on a flat surface (a handy thing when you're working on grimy airplane tray).

As you can imagine, a design like this requires a reinforced hinge, along with extra space inside the chassis; for now, at least, Lenovo doesn't know how to put a keyboard like this in a super-skinny machine, which is why you're not going to find it on the new Yoga Pro, the replacement to the Yoga 13. At any rate, it's not a perfect solution -- you can still feel the individual buttons -- but at least they stay put. Also, it works much more quietly than you might expect. To be fair, our expectations were low in that regard: when Lenovo first told us it was working on a self-flattening keyboard, we envisioned a machine with a noisy motor inside, similar to the failed Acer Aspire S5. After watching a demo, though, we were impressed by how little it creaks -- and a Lenovo rep promised it would make even less noise by the time it ships.

http://www.engadget.com/2013/09/05/l...&ncid=rss_semi