Scott Weaver and his toothpick model of San Francisco.
"He started building the toothpick structure at age 17 and 3000 hours and over 30 years later he finished his brilliant creation.
The model alone had us impressed, but its functionality blows past any and all expectations. A ping pong ball is placed at entry points in the model and rolls along the streets of San Francisco. The structure stands 9 feet tall and is 7 feet wide." ~Apartment Therapy
Source: The Experts Agree