Sometimes, when you've worked with people for a while, you get to know what amuses them. At a previous job, someone mentioned Bolivar, Missouri. I thought, "If I know this co-worker, he'll start singing in 5, 4, 3..."
As expected, he began singing to the tune of Jackson Browne's "Boulevard," "Down on the Bolivar, they take it hard..."
It still unnerves me that I was able to predict that.