This is a motorized door lock inspired by The Amazing Spider Man. It makes use of a rack and pinion which converts the rotary movement of a servo motor to linear movement. Once the rack is extended, it fits into the "rack holder" which is screwed into your door frame. This model requires the use of a standard sized 180 degree servo motor (40.8 × 20.1 × 38 mm). If anyone needs the model to be updated to fit a smaller or larger motor, please leave a comment and I will upload the new models.
UPDATE: The motor holder has been updated and redesigned to increase the strength and fix some modelling issues.
UPDATE 2: The chamfer on the Gear model has been removed. The object will now print without the use of supports or slight drooping.
Some coverage by Makerbot themselves: http://stories.makerbot.com/post/95939577127/locking-a-door-like-spider-man