noun. A combination of the words geek and weakpoint.
A subject which causes a seemingly normal person to immediately turn into a complete geek. This is a topic they do not usually discuss, but, when mentioned in front of them, can result in (but is not limited to) the mentioning of random trivia about the subject, an account of experiences with the subject, offers to share material about the subject with the person who mentioned it, etc.
In theory a geekpoint could be anything that an individual has an overwhelming knowledge of. Though it is usually defined as something related to movies, TV, games, or books.
John: So what did you do this weekend?
Jack: Nothin much man, I saw Star Trek. It was pretty cool.
John: I don't know (list reasons why he didn't like it because of differences from the series).
Jack: (about 10 minutes later) Dude, chill. I just wanted to see the movie. John: Oh sorry, that's my geekpoint.