I'd have to say for me it's Fight Club, because I am single and just totally love that movie. I don't want to be reminded of how truly lonely I am on the most "romantic" day of the year... (Movie spoiler warning!) I'd rather see a crazy split personality dude attempt to destroy society as we know it. If I wasn't single however, I'd probably be watching Scent of a Woman, or Terminator 2. Have you seen this boy?? HOOOWAAAA!!! I'll be back.
