While rummaging through the toy section at the Arc the other day, I spied a busted-up remote control car. It had clearly been stepped on or otherwise abused since parts were missing off the body. Plus, the remote control unit was nowhere to be found. So I was I able to get this gem for just one dollar.
When I got home, I took off the cracked body, removed the control board from inside, cleaned the battery compartment where the batteries had leaked and made sure that the motors worked. Then I rubber-banded an Arduino and motor shield to the top and mounted an infrared distance sensor to the front. A few minutes of programming and voila… what used to be a busted RC toy was now an obstacle-avoiding robot. Go watch the little guy in action. http://www.youtube.com/watch?v=6C_YUy8C0T8
While it may not look any prettier than when I got it, the result was well worth the dollar I invested.