Here's a BCS nightmare scenario for you -- two non-conference champions playing for the title. Not possible, you say?
Here's how it happens:
1 LSU loses to Arkansas, thus knocking the Tigers out of the SEC title game
2 Alabama loses to Auburn, thus ensuring that Arkansas goes to the SEC title game
3 Georgia upsets Arkansas in the SEC title game
4 Baylor upsets Oklahoma, meaning OU has two losses
5 Oklahoma then knocks off Oklahoma State, meaning the Big 12 champion has two losses
6 Arizona State beats Oregon in the Pac-12 title game
7 South Carolina beats Clemson, giving the Tigers two losses
8 Clemson trips up Virginia Tech in the ACC title game, and the Hokies are a two-loss team
Put all that together and the top two teams (though I don't know in exactly what order) will be LSU and Stanford. Oh, and Boise State would be third.