Yup, that's the one I'm going with... An interactive Light Table. I have seen it done on Youtube and they just look totally awesome. I've seen one person basically turn a coffee table into an interactive one that lights up the areas you move your hands or objects onto the table. And another where someone built individual boxes into the table with independent rgb modules to light the tables to do different effects and even some games with it. Both use the same concept. You basically use IR Sensors and emitters for proximity and leds for visual feedback for awesome results. Again yes I've seen it done on youtube and words can't describe it, it'll geek you out so bad. And if you ask well if it's already on youtube, then Why? I kindly respond with Why Not? 
