There are “unpaid” internship listings at every one of the top business schools, and are offered as such since there are students that are happy to take them either for course credit or just for work experience. I’ve seen the job listings at virtually all of the top business schools so can confirm they exist. As far as “reputable” goes, you’ll have define what that means. The demand for hedge fund jobs still far exceeds the supply and when people are willing to do whatever they can to get in the biz, that’s what gives rise to these unpaid opportunities. Most people can’t even get a look from a fund, so students and recent grads will do what they can to get experience and a recommendation in hopes of something more financially feasible in the future.