Random idea, but what if you could combine market data with news articles, and (obviously only for the past few years) data from blogs/reddit/hn/twitter/etc.? Sometimes there is fascinating insight to be learned in obscure places on the Internet (hn itself being a great example); I imagine a system that would collect and analyze that kind of information would be quite interesting, despite the huge amount of noise. Such a hypothetical system reminds me of this story: https://www.facebook.com/notes/robin-sloan/julie-rubicon/985...