Pac-Man reenacted by humans.
UGLi (Undergraduate Library), University of Michigan, 2005.
http://www.boingboing.net/2005/12/21/pac-man-reenacted-by.html
http://www.youtube.com/watch?v=0FGzOoVvo6w (Thanks, BoingBoing!)

Denver Public Library, 2007. Includes riding on book trucks, making book angels, and reading books. http://www.youtube.com/watch?v=tFDo1dt0_Lo

Hennepin County Library, Minneapolis, 2007.
Emily Lloyd’s blog

Second Life Libraries, 2006.
http://www.youtube.com/watch?v=jTQkzfz5osQ
(A virtual shenanigan.)

Lest the Keepers of the Book Wreak a Terrible Vengeance.
Boulder Public Library, 2007. Pro-librarian conversation.
Overheard in the Office Also: http://www.overheardintheoffice.com/archives/005029.html (and all librarians can tell you about unusual things used as bookmarks, like condom advertisements or strips of bacon.)

From Weird Al Yankovic’s UHF, 1989. http://www.youtube.com/watch?v=mZHoHaAYHq8& (A fictional shenanigan.)

Extended computer start-up sound from prangstgrüp.
Columbia University library?, 2005.
http://www.ronniedelcarmen.com/blog1/2005/10/prangstgrup-videos-if-laptop-startup.html
http://www.youtube.com/watch?v=Mt1bgsvsWms

Monty Python’s Flying Circus, series 1, episode 10, 1969.
http://www.youtube.com/watch?v=ukJmF6f0JdQ
(A fictional shenanigan. Thanks, Ahniwa Ferrari!)

Unknown college or university library, 2007? http://www.youtube.com/watch?v=pyLTqBARFt8 (Thanks, Ahniwa Ferrari!)

Library unknown, 2006?
http://www.youtube.com/watch?v=LdgdBOTUSqg
(Thanks, Ahniwa Ferrari!)