Crazy for Crop Tops

The hot new accessory in Hollywood? Apparently it's abs. And if you've got 'em (which Selena Gomez, Diane Kruger and these other stars certainly do), there's no reason not to flaunt 'em in a short shirt. Now excuse us while we do 100 sit-ups...

ALICIA KEYS

This girl is on fire … and our stomach muscles are burning too just thinking about what Alicia's daily workout must be like.