It is called the Ripsaw, a developmental unmanned light tank built by the Howe brothers in 2000 as a small family project. It is able to accelerate to 60 mph (100 km/h) in about 4 seconds. The vehicle caught the interest of the U.S Army in 2001 during a Dallas vehicle show. The Ripsaw can be built for about $200,000 - $250,000.
A human driver is inside of the vehicle in a video, but that was for early testing. The preferred current version is a UGV (unmanned ground vehicle) that is radio-controlled.