Jeff wrote this Instructable detailing the build of his LED beer pong table project:
This instructable will guide you through all of the steps to in order to create a one-of-a-kind beer pong table complete with cup detecting RGB pods, automatic ball washers, a 32×12 ping pong ball LED grid, side LED rings for spectators and an RF interface to communicate wirelessly with a PC! It will teach you everything from theory of operation to modifying the table to suit your needs. First, I will take you through the modification and wiring of the table before we dive into the software side of things.
Check out the video after the break.