Owen Sims sent me this interesting article which looks at whether Twitter can predict the stock market. Johan Bollen, a computational social scientist, used algorithms to measure the mood and sentiment of tweets in order to to gauge the public mood. The measure he developed was correlated with subsequent movements in the stock market. This correlation may be spurious, but behavioural economists have increasingly been interested in how public sentiment affects asset markets and they have used the news media to get a handle on sentiment. See, for example, Paul Tetlock's work in this area - click here.
