Alright, so I want a small, {inch or two}, sensor of some sort that, when bumbed, {just slightly}, sends out an electrical signal. What should I use and how much is it?

 

Thank you.

I saw a neat, cheap version of this on a toy not long ago. It's shaped like a bug's antenna (it's a toy bug), but at the base is a weak spring. In the center of the spring is a straight wire. When the antenna is pushed, the spring at the base bends, causing it to contact the wire and complete the circuit.

Ha, that is exactly what I visualized something to work as, but I would rather buy one at the moment just for better quality, but I guess I will make it myself thanks.