I remember seeing this dairy-themed rock opera parody when it was first released in 2009 and features "White Gold" attempting to rescue his beloved from an evil megalomaniac with the help of the mythical Bovinia, all the while promoting milk's health benefits. It was originally created as part of a rather exuberant marketing campaign by the California dairy council and has a heavily pun-filled script that I found to be hilariously awful, if not quite awfully hilarious. Anyway, I can think of worse ways of spending 22 minutes.
(posting this because I keep misplacing the link)
A few weeks ago we happened to visit the Smithsonian National Air and Space Museum and had a great ol' time. During the afternoon, while we were in one of the exhibits, I heard some music playing and thought they were starting to play some festive music because it was coming up to the holidays. Soon afterwards the music stopped and people could be seen walking around carrying musical instruments. I forget what I was doing at the time, or where I was going, but evidently I was distracted as I quickly completely forgot about seeing the musicians. That is, until today when my father-in-law told me about this video of a flashmob at the museum. I don't know if they did it multiple days, I suspect they did, but it was cool to be there.