All of us experts in the magazine business used to know that sex was what sold. Now it's celebrities on covers that drive newsstand sales. But which ones really push the hot buttons of consumers at supermarket checkout lines? Forbes magazine studied the newsstand sales of six top celebrity magazines and found that the number-one selling celebrity is....Jennifer Aniston. She was followed on the list by her own ex-husband, Brad Pitt. (We sense a pattern here.) Surprisingly, Pitt's current wife, Angelina Jolie, came in fourth place, after Scarlett Johansson.