The best one out there. The book is structured around areas that will be tested when going for a quantitative interview.
Infu
The hardest part was faking like I hadn't heard the questions before. I was amazed, this book got me a flyout at a prop trading firm, and very nearly got my the position--on my first qaunt finance interview ever.
Dustin E. Currie
A must have for everyone who wants to interview for a quantitative finance position. I was told by a recruiter that the folks in Goldman Sachs often pick original problems from this book!
Kai