Twenty years from now, you’re going to find yourself huddled around friends — remember friends? — at a bar — remember bars? — in downtown Boston. You’re wearing a Celtics home whites jersey over a long sleeve t-shirt, sipping your second beer as tip-off looms. Since this is a fantasy, guess what? It’s also Trivia Night, and you and your team have a chance to win tickets to Friday’s game. So far, you’ve nailed questions on “The Office,” MySpace Tom, and the diameter of a standard dartboard. The last question will, naturally, be about the Celtics. You were made for this.