Interstellar Pig is a 1984 young adult science fiction novel by William Sleator. It features a young teenager named Barney who is bored at his parents' beach house one summer until he starts hanging out with his three older neighbors (Zena, Manny and Joe) and playing this game called "Interstellar Pig" with them. The game features lots of different alien races competing with one another to find the Piggy -- if you don't have the Piggy when time runs out, your planet is destroyed.
These neighbors are also terribly interested in the legends surrounding Barney's family's house and the sea captain who used to live there. Barney eventually thinks he's figured what they really want, but is just knowing going to be enough to stop them?
Many readers of the book seem to have tried to make their own version of the Interstellar Pig board game, and at least one reader says there is a great similarity between the game described in the book and the late 1970s SF board game Cosmic Encounter (enough to make him think it might have been an influence on the book).
In 2002, Sleator published a sequel called Parasite Pig, which I haven't yet read.
Nickelodeon Films and Paramount Pictures have an option to make the book into a film, but all the sources I can find have been saying (from 2001 when I first wrote this to the update I am doing in June 2004) that the picture is still in development. Damon Santostefano is supposed to direct and Phil Morton to write the screenplay. Nickelodeon also partnered with THQ to put out a video game for the Gamecube called Interstellar Pig (or Interstellar P.I.G.) which was supposed to come out in the first quarter of 2003. However, I can find no references to it ever actually being released.