In regards to hooligans idea of using a smoke detector , perhaps Technopro could detect candle smoke (Birthday boy )or incense! and create a funny/cool behaviour.......not to mention a pizza smoke detector hahah....I can just envision a Wall-E frantically going in circles yelling out " your pizza is smoking(another pun)

Technopro, Everyone likes various dancing modes on robots, lots of requests. After numerous demonstrations, thats what people ask for.

Dave S, Sure like the cartoon, I can relate, very creative response. Steve S

Thanks guys! what I was thinking is a temperature sensor so that when its hot wall-e can spray his water gun arm(that ill build) and someone when he's told to track faces.

light density! so the wall e knows when the light are on or off. or a fingerprint sensor....

or.....the "eyelids" cut them out and add micro servos....make his face as animated as possible.

I will upload a video of my smoke sensor tonight....im in california so it might be a little later in the evening.