[youtube=http://www.youtube.com/watch?v=Smai_Z_galE]

iPhones and iPod touches have many advantages over the plain iPod. Have you ever wished you could advance tracks without looking though? That is a perfect example of where the current display/ input trends are lacking. There is no tactile feedback. [Chris Harrison], a Ph.D student at Carnegie Mellon has been working on an alternative.

His displays are rear projected and multitouch like many of the other multitouch systems we’ve seen. However, his also offer tactile feedback by changing their physical shape. Much like a vac-u-form, he is using vacuum to deform a flexible surface over different shapes. Not only are they able to do simple 2 state systems where you have smooth, then vacuumed, they can also do a third state by pressurizing the inside of the display. You can see several variations in the video.