Bill Murray Fills in For Harry Caray During Cubs Broadcast, Hilarity Ensues
This is why YouTube is the greatest invention ever. (The wheel? Yeah right.)
Here for you are five separate clips (first one via Fark) of Bill Murray filling in for Harry Caray during a Cubs broadcast in April of 1987. Steve Stone holds his own here and basically acts as a prompt for Murray's stand-up comedy routine.
The above clip is the pregame rundown and the four after the jump are at various points throughout the game.
Drop what you're doing at once and dive in, folks. This is of far more importance than whatever else you could be doing at the moment.