It's winter. You're a cyclist and you want to train, but it's cold, wet, and slippery outside. Indoor equipment is expensive and you're hungry for data. CritSim gives you that data by accurately modeling a race using your bike that has sensors attached and mounted on a trainer. Now you're in a virtual cycling race! The sensors can detect whether you are turning based on how you shift your weight, and how fast you are going based on the sensor on the back wheel.