Here is another treadmill designed to take your cardio and endurance training to the next level. The Tru Grit Fitness Curved Treadmill is a self-propelled exercise machine with 6 levels of resistance. It has a battery powered screen to show time, distance, pace, speed, calories, and interval training modes.
This treadmill has a commercial grade aluminum and steel construction and can handle up to 400lbs of weight. The above video shows it in action.