hi, i read ur post and i was tolly shocked liek february! damn thats a long time ago and no1 has answerd.
well, here i a cool DIY robot sensor thats used alot in BEAM robotics (robots that look like stuff from the nature like bugs and stuff)
hope the picture works tho,
well, the point is that you take a spring from an old pen, a stiff wire, some insulating (duckt tape is very good) and some time.
tape arround the stiff wire so it fits in the spring, attach another stiff wire to the end of the spring.
so when something touches the wire conected to the spring, the spring wil bend and touch the stiff wire in the middel.
if you make it right it will look very insect like