In my opinion it would be Basic Instinct. I watched it a couple of nights ago, never watched it before and while it's not a bad movie, I found it quite meh.
I think it got the attention that it has pretty much only for the shock value and for the fact you can glimpse Sharon Stone's fifi for a half-second. None of the characters were likeable and I couldn't root for any of them.
Wife says that a German movie explored the concept better in the 1980s, but for her everything German is better so I don't know how much water her statement holds.
What about you?