My apologies if there's another 6 degrees (
http://en.wikipedia.org/wiki/Six_Degrees_of_Kevin_Bacon) thread, the search function's not working right now.
While watching a video of Moon over Bourbon Street that Bob Lion54 linked, which featured scenes from the movie Interview with a Vampire, I noticed Tom Cruise, Brad Pitt, and Christian Slater were all in the movie. Tom Cruise was in "A Few Good Men" with Kevin Bacon, which reminded me of the game.
It works like this if you're for instance trying to link Carrie Fisher to Kevin Bacon:
Carrie Fisher was in Star Wars with
Harrison Ford was in The Fugitive with
Tommy Lee Jones who was in Batman Forever
Val Kilmer who was in Heat with
Robert Dinero who was in Sleepers with
KEVIN BACON!
So, in this scenario, Carrie Fisher has a Bacon number of 5, though there are shorter routes that would give her a lower Bacon number--how small can you make her Bacon number? How about Katherine Hepburn? Your favorite actor/actress?