There are already plenty of tools that can guesstimate how many calories you can burn by walking and running for a certain period of time. EPFL researchers are taking the idea to the next level by developing an avatar-based software for this very purpose. It looks at how people walk in order to predict their energy expenditure.
The avatar is essentially a torso with two legs with feet. Users can enter their height and weight and set the walking speed, distance between their feet, and other parameters. The # of calories burned and energy consumption are displayed in real time.