Hedge fund manager Seth Klarman is enjoying unprecedented popularity as an author of a book that has been out of print for 15 years. Back in 1991, Klarman published Margin of Safety: Risk Averse Value Investing Strategies for the Thoughtful Investors, and it hardly made waves. Today, there is a flood of interest in the 249-page volume that went for $25 when it debuted and is currently fetching up to $2,500 a copy (Amazon.com reportedly has a steal of a deal at $700). Why is the book, in high demand on college campuses, so hot now? According to BusinessWeek Online, the book has taken on cult status, especially among those who want to get jobs at value-oriented firms. One new MBA holder told the magazine, “You win serious points for talking Klarman. It’s pretty much assumed that you’ve read [Benjamin] Graham and [David] Dodd [authors of Security Analysis] and Warren Buffett.” Klarman, who is now president of Boston-based Baupost Group, did not comment on the phenomenon, but the Web site described his investment prowess as a reason why people have taken a keen interest in the book. For those who don’t want to plunk down the big shekels, one may try eBay: Recently, one book owner offered to rent it out for $75 a week.