HINDUNILVR/ NIFTY is almost a mirrorimage of NIFTY. I plotted various other stocks against NIFTY but cound't see any such pattern. One thing that can be derived is, whenever NIFTY goes down, HINDUNILVR usually maintains the level and in many cases it starts to move up. Example - recent fall of NIFTY.
Let me know what you think! Please do hit me with other interesting observations you saw in the market.