This site is amazing! Some dudes wrote a code that scans blogs for statements that show how a person is feeling. They are presented in this massive moving dot thing where each particle represents a feeling posted by someone on their blog. It's freaking cool and I love the colors.
Feelings are broken up into five different areas: madness, murmurs, montage, mobs, and metrics. You can control the population of feelings with filters at the top. Oh yeah, they also turned it into a book, find it here.