Liquidware has a great touch shield out for the Arduino. It’s a 128×128 OLED display with a resistive touch screen on top. It can hold up to 60 full screen images and only uses pins 3 and 4 on your Arduino. It may seem pricey at just over $100, but it’s worth every penny considering everything that’s packed onto that little shield (they even managed to squeeze in 16MB of on board video ram). You can pick one up here and you can look at the open source code here. If you end up getting one, let us know what you end up building with it… I’m off to buy one now!