Professor Ronald Rivest provided invaluable assistance as Roger's Masters and Michael's Bachelors thesis advisor and caused us to think long and hard about our design decisions. Professor Michael Mitzenmacher made possible David's involvement in this project and provided insightful comments on information dispersal and trading. Beyond many suggestions for overall design details, Brian Sniffen provided the design and background for the trust system, and Joseph Sokol-Margolis was useful for considering attacks on the system. Adam Back and Theodore Hong commented on our assessment of their systems and made our related work section much better. Furthermore, we thank Susan Born, Nathan Mahn, Jean-François Raymond, Anna Lysyanskaya, Adam Smith, Brett Woolsridge, and our anonymous referees for further insight and feedback.