We've had our far share of dumb things happen but yesterday takes the cake.
We were setting up in the basement for our Big/Little revealing and were just about done when we noticed water dripping out of the ceiling right in the middle of the room. All of a sudden the flow of water increases and water starts gushing out of the ceiling and flooding the floor. We had to grab all of our stuff and run it up stairs and call maintenance. We moved our ceremony upstairs and during the middle, the maintenance people got there to fix the toilet, so we're trying to do our nice serious ceremony and we hear them talking, "yea, it looks like the toilets leaking". Kind of killed the mood.
It was just a good thing it happened before we started the ceremony. The little sisters would have been standing directly under where the leak started. That would have been horrifying for them.