GAP LINE:
Plots the cumulative line of gaps to see extremes in psychology.
Plenty of Gap-UP's where the Open is higher than the previous bar's close get the market excited.
Plenty of Gap-DOWN's where the Open is lower than the previous bar's close get the market scared and depressed.
Look for the Gap Line to peak prior to an important peak in the market and vice versa. Look for a low in the Gap Line prior to an important low in the market.
Simple, but effective.
Tim