My YouTube user name—seamuspad
I wanted to watch a “public service announcement” with Bobby Bittman (Eugene Levy in his SCTV days) at the "libary," but I couldn’t get it to play. Tragic! I was able to view it a few days later, though: http://youtube.com/watch?v=aPliZ7OvRYQ
Here's a real public library PSA: Pretty good picture and sound quality, probably because it’s a professional job. Others I've watched aren’t so good.
Everybody loves the movies, right? And it's even more fun if you or your friends appear in them. The Nebraska Library Commission spot is a good example how libraries can use YouTube for PR. Other possibilities: programs, book talks, board meetings, etc.