Very cool! I've been interested in this area for quite some time. Here's one guy to built a hedge fund around the quantification of investor sentiment using online data (http://www.popsci.com/scitech/article/2008-02/money-minded-h...)
"MarketPsych ran an audited hedge fund (MarketPsy Long-Short Fund LP) from 2008 through 2010, which beat the S&P benchmark by 25% during its lifetime."