CNN has a "Fear and Greed" index for the market. They use some indicators to attempt to sense how fearful or greedy investors are at the time. They then display their results on a 0-100 scale, 0 being the most fearful and 100 being the most greedy. If investors are greedy stock prices should rise and if they are fearful stock prices should fall. So, if someone traded based off of this index for three years, how would they do?
I extracted data from CNN's site using a plot digitizer (pretty cool). My algorithm is pretty simple. It buys/holds when the index is above 50, and sells/holds when the index is below 50, though that number and the security it trades can easily be modified.
Play around with it by cloning it below and let me know what you think.