A Little Knowledge is a Dangerous an Entertaining Thing

I just went to Amazon.com to buy a long overdue gift for a friend and decided to check out what Amazon's recommendations were for me based on its intimate knowledge of my psyche and needs. Numbers 1, 3, and 5 were all economics books while number 2 was a corporate finance text. Obviously, they've gotten word that econometrics make for great summer reading. Number 4 was Pride and Prejudice, which I actually should probably buy since I haven't read it since high school, but how did they know that?

Isengard strikes again...