Over at Animals and Us my friend Hal Herzog has some fun with the NGram viewer--a tool that allows you to quickly and easily search and graph the presence of any word (or combination of words) in over 5 million books spanning two centuries. Hal finds that chicken is now a lot more popular than beef. He also documents the similar rise in the gay rights and animal rights movements. Most importantly, he demonstrates that, contrary to what John Lennon said, the Beatles were never more popular than Jesus.
The possibilities for uncovering trends in politics are limitless--for a great example, see here, Although I wasted far too much time goofing with this, the graph below (popularity of various southern states over time) perhaps the most interesting one.