Distributed decisions: When will Halloween be celebrated? [thanks Kevan] presents simulations run to examine how the following question is answered: "With no central planner to dictate when the celebrations shall occur, how can everyone collaborate to celebrate at the same time?" Excellent, and points to an interesting way of making decisions: instead of explicitly building the feedback and amplification mechanisms in software to making a decision, bootstrap off existing social structures, and provide conduits for those message types instead.