Doodlebug Drawing Robot
The only electronics are a sound chip. Just a motor driving a wheel and oscillating the arm linkage. You can adjust the orbit radius manually via a knob on the bottom. My twins love it. I figure someone here named Gareth (who has drawn amazing geometric patterns with UV LEDs) might get a kick out of it. ~$18 on Ebay from Tiger Direct: http://www.ebay.com/itm/351077651506
