One of the things I love about Amazon.com is how it recommends everything about a given subject if you do anything that suggests an interest in it. For example: I just added The Art of the Steal by Frank Abagnale (the Catch Me If You Can guy) to my Recent Reads list on Amazon (which should be linked over on the left if I've not screwed that up).

I now get recommendations for every book written about scams, frauds, protecting your identity, and so on.

You can imagine how the page looks after writing questions. The suggestions after researching a bonus part on Kim Catrall's book about female orgasms was, well, let's just say educational.