Check out the Synaptics ForcePad. It is super thin (less than 2.8mm) and is pressure sensitive of up to 1000grams. It can recognize 5 fingers and does not have any moving parts.
BTW, the above is a Lenovo U300S with Synaptics ForcePad retrofitted onto it. Basically, the ForcePad is a large touchpad. Most of the features are software based and thanks to the capacitive (up to 5 points) and 64 discrete pressure levels (at 15 grams each), it will definitely benefit OS like Windows 8.
Here is a graphical look at how thin the ForcePad is.
According to the video, because the ForcePad is thin, it is able to make out precious space for battery or a thinner chassis. And in the video, it shows the benefit of using the ForcePad on a flight simulator software. Check out the video.
In addition, AnandTech also mentioned ThinTouch, an ultra thin keyboard with capacitive touch.
And if you really want more details and actual footage of how it works, here is one from AnandTech.
Hopefully, we can see more of this technology on OEMs. I am sure many will like a thinner laptop.