In a mostly irrelevant personal note Grant and I graduated in Numerical Mathematics from BYU the same year; there were only a handful of us so we spent a lot of time together in the top floor of the Math/CS Building. He was working on this during a big chunk of our undergrad and I think some after as well. I'm embarrassed to say I haven't taken the R plunge yet (SAS and STATA right now) but when I do I'm sure this will be my starting point.