Why Popcorn Costs So Much at the Movies, and Other Pricing Puzzles, by Richard B. McKenzie (Springer-Verlag).

Written by an economist for smart people, Popcorn unpacks pricing puzzles taken from real life, from the age-old debate over ending a price in a 9 to charging $10 for a bucket of movie theater popcorn. McKenzie never trivializes or condescends, and he steers clear of making controversial statements just for the sake of publicity. Best of all, he is scrupulous about exploring multiple theories for each issue raised, avoiding the mistake, made by so many writers, of telling only those anecdotes that support the book's main thesis. To an entrepreneur facing the mystery of setting prices, this book contains a wealth of important ideas.