The CNN Greed & Fear Index is one of the best signals I have seen. I have followed it for some time and anytime it gets above 90 to Extreme Greed, a sell off or pull back occurs within one week. This has even been the case in a market manipulated by low interest rates and Federal Reserve massive printing of money. The Greed Index today just jumped over the 90 level, settling at 91. This to me signals a possible reversal in the coming days.