The one thing better than picking winning stocks is being able to piggyback on people who pick them, Jim Cramer told viewers of his "Mad Money" TV show Thursday. Financier Carl Icahn, who recently made a great call by getting into Lear ( LEA), previously and "perfectly" made money with Time Warner ( TWX), Cramer said. "When you catch a guy like Icahn who has been on a winning streak, people must piggyback off of him," he said. Right now Icahn is buying WCI Communities ( WCI). However, before buying WCI, a good piggybacker should first understand the way Icahn is thinking, Cramer said. (See what else Icahn is buying by checking out his portfolio on Stockpickr, a TheStreet.com affiliate.) WCI is a homebuilder that owns 86% of its properties and creates upscale communities. But the real reason Icahn likes it is because WCI is selling below its book value, Cramer explained. WCI is sitting on a big pile of real estate, and Cramer believes that the stock should ultimately be valued more than its properties.