I really agree Dredd would be great for the marathon especially since it was not a success in theaters which means it'd be new to a lot of the crowd. Very violent so late night showing.
Chronicle even though it was a hit would also go over. It's a clever use of the found footage cliche.
A documentary just came out called 'Men In Suits' not sure it's been mentioned, it's a look at the men inside Godzilla, The Creature, Alien, Predator, Robby the Robot and others. You can see the trailer here.
http://www.youtube.com/watch?v=0u54NHkkWUY