Here's a video of a bar graph displaying in real-time the output of an accelerometer. The coordinates are read through the Arduino base, and then passed through to the TouchShield. All the code for the application is like ~30 lines. I'm still working with Chris on a version that shows both X and Y values separately, since this one only shows a cumulative G force calculation:
...and here's a video of the Arduino with a simple application to show off what a touch screen looks like - it kinda feels like plug and play, but not really: