Sony demonstrated their touch panel which can detect the pressure you’re applying that could give a z-axis reading.
According to what I’ve read, devices using this touch panel might costs an arm and\or a leg. But if you ask me, it worth what you’re going to get since, well, you can do so many things with this panel. For example, a 3D desktop environment for mobiles (Something I came up with from the top of my head).
Sony would want to use this panel as soon as possible. I just hope they kick in a kickass WinMo7 with this screen… Oh boy, that’ll be so much PHUN!!