Heh - looks like things just got even easier - seems that Diffused Illumination is the "new thing" in terms of Mulit-Touch and the best bit is its even easier. All you need is the acrylic sheet, your tft matrix, a camera, a "diffuser", a light (so you can actually see the tft!) and... an IR light source (you can either make this yourself or buy one - "IR Illuminator" on Ebay. Not sure of how exactly this stuff works, but work it does so plans have now changed a little....

Oh the fun to to be had.