Inspired by, but not entirely appropriate to post to the Social Systems thread.
Reading that thread made me remember one of the most satisfying and enjoyable 'social manipulation' sequences I've ever had on a MU*. It was on Darkwater (Changeling version, using CoD rules), and used the Doors system. My character, an underworld smuggler with some legitimate business concerns as cover, ended up crossing/getting up into the face of another character. Both were Lost, and the other character decided to put my character over a barrel by undermining and influencing his mortal connections in order to get him to do...something. I've actually forgotten what. So, we used the Doors system, and I laid out and ran several mini-scenes where the character had a chance to meet up with specific connections my character had, and woo them to her side. Each success opened a door on my character, and when all doors were opened, she confronted him and revealed just how screwed he was, and got the concessions.
It was great fun, and I loved having a chance to explore that sort of social maneuvering. And my character ended up respecting and liking hers a great deal, because she was both clever, and gracious in victory. It was just fantastic, even though my character 'lost'.