After reading critique after critique of all the isms present in James Cameron's Avatar, ensuring that I will not be seeing it any time soon (in theaters, anyway), I came across this nifty little rule from a 1985 strip of the comic Dykes to Watch Out For in which a character details her criteria for movies that she is willing to see: The Bechdel Test
There are only three parts to the rule:
1. There has to be at least two female characters.
2. They talk to each other.
3. About something other than a guy.
It's depressing how many of my favorite movies don't make one or more of the criteria (and I know Sherlock Holmes will probably blow it big time and I'm still going to see it), and a lot of the films that do can hardly be touted as feminist, but it's a great (if simplistic) start for eyeballing gender politics in film.