Readingradar.com is an interesting new "mashup" for people who love bestsellers.
What's a mashup? It's a Website that combined content from two different resources into a brand new site. Readingradar.com combines the New York Times bestseller lists with customer reviews, and other material from Amazon.com. The resulting Website brings together a lot of information about individual titles, in an easy to use interface: just click on the name of the bestseller list, and browse the ranked titles.