It's hard to tell if a smart belt is a perfectly reasonable idea or a completely ridiculous one. On the one hand, belts are common, unobtrusive, and rest in intimate proximity to some of your most vital organs. On the other, it's a belt. And that very unobtrusiveness is an invitation to make things big, weird, and gaudy.

Belty is definitely the first two of those things. A bulky metal-and-plastic prototype, it's developed by French company Emiota and tentatively set for release at the end of the year. Partly, it's a health tracker — it collects data with a built-in accelerometer and gyroscope, then syncs wirelessly with a mobile app. This means it can track your waistline over time, keep tabs on your exercise, or check how much you sit and suggest you take a walk if you get too sedentary. But unlike your basic fitness watch or medallion, Belty also features "autoadaptability."

What does that mean? It means that the belt is equipped with tiny motors, which can automatically expand and retract it. If you sit down, the belt will detect it and relax, a feat accompanied by a tiny whirring sound in the CES Unveiled demo. By tracking tension and activity, it will also theoretically detect when more support might be helpful, tightening up on its own, or find the optimal belt size based on your waistline. Belty is going to undergo aesthetic changes before launch, so we're unclear on whether the whirring will eventually disappear. Right now, with the right clothes, you could probably convince at least a few people that you're an extra in Westworld. Likewise, the price is unknown, but we're told that it will be a premium product. Motorized belts don't come cheap.