For those who are insecure about their yoga skills and lurk in the back of the class, your latest nightmare is a pair of pants that know when you're making a mistake.

How it works: Three sensors — one at your ankle, another behind your knee and a third at your hip — can tell whether you're doing downward dog, or any other yoga pose, correctly. If you've got it, the sensors vibrate to congratulate you! If you're not quite there, the app, which is linked to your pants, will tell you how to adjust.