There is a bearish gartley pattern in the SPY. This pattern is also seen in the well diversified NYSE index. This particular pattern gave a clue it might work with the 2 candlestick dojis at the D point of the pattern.
The sign of weakness today seems to confirm that this pattern is working and could lead to heavy selling going into next week.
Note that a harmonic pattern also displayed itself at the 1987 top and there was also a DOJI near the end of the pattern before the final crash leg unfolded.