This project is very dear to me as it was something I created in grade 11 with a school friend of mine. Our goal was to build the first multi-touch surface table that, at the time, didn't require any sensors for detecting touch. We were able to achieve this with a piece of paper and an infrared camera that we hacked out of a USB web-cam.
“The "Ant" was a name that was coined after the two creators-- Anuj Vaishnav and Nirman Dave. An acronym for Anuj, Nirman, Table. The Antable.”
Here is a quick video with the table in action.