What's a little probability and statistics among friends?

Yesterday Chris and I spent a long time compiling a guest list for our wedding. We were slightly alarmed at the nearly 250 people we came up with. The only thing more terrifying than the total number is the manner in which we dealt with it: we went through the whole list and assigned probabilities to all our potential guests: 1 for almost certainly attending; 0 for almost certainly not; and 0.5 for possibly and/or will only fill one of the two slots allotted (i.e. people unlikely to bring dates). It was totally dorky and totally amazing, because taking probability into account, our guest list was cut in half. It turns out that we don't think our extended relatives love us very much, but we have higher hopes for our friends.

Speaking of dorky! This coming weekend is Puzzlehunt, this weekend-long team puzzle-solving event at Microsoft that happens quasi-annually. I'm very excited. Now if only we could find a way to codify puzzle-dorkiness in a wedding cake.