QS Contest: What Would You Do With a Body Media Armband?

A la Google Glass, Gary Wolf announces a Quantified Self contest/give-away:

In conjunction with our upcoming QS Europe Conference in Amsterdam on May 11/12, our friends at BodyMedia have agreed to donate a complete personal SenseWear System (retail price $2,500), a state-of-the-art wearable sensor that allows raw data output. That’s going to be our prize. So if you have good questions, we can supply you with a way to collect the data.

The best answer wins the sensor.