The design team at the Canadian company Bombardier chose very light materials for the EMBRIO, including aluminum, magnesium, and nylon, resulting in a total weight of merely 360 lbs. (163 kg). The EMBRIO will use a number of advanced automotive technologies, such as infrared night vision, a digitally encoded key, and active suspension, which can vary its damping rates based on road conditions. Balance is achieved via a network of sensors and gyroscopes. Although the designers believe in the gyroscope's ability to stabilize the vehicle, they did keep a longitudinally smaller wheel that operates similarly to an airplane's landing gear, retracting when the vehicle slows to 12 mph (20 km/h).
The Bombadier EMBRIO received the Industrial Design Society of America & Business Week Magazine's Gold Award back in 2003 and is still merely a concept, which may or may not materialize. Regardless, it stands as a testament for the creativity of its designers.
More information on the EMBRIO concept from the Bombardier website