It can't hurt to see where the smart money is going.It's not cool to peek over the shoulder of the smartest kid in your class to see what answer she gave for question No. 7 on a test. In the same spirit, you might peek to see what some of the richest investors have been buying -- and that's far less problematic. It's natural, in fact, to wonder where the supposed smart money is going.Here, then, are some relatively recent purchases made by some billionaires. I found them by checking their most recent 13F fi ...