Okay, the ceremony of the ducks leaving the fountain and getting on the elevator is going to seem cheesy if you've never seen it...but you gotta see it at least once. It's simple, sweet, and doesn't take long. It's also free.
They do this daily at 5 o'clock, with the narrator and ringmaster giving a great detailed account of how this tradition came to be. You better arrive by 4 p.m. though, if you want to get a good seat. Arrive early, order a beer, and enjoy