This has nothing to do with libraries, mind you, but I’d love to see a library website fall apart like this retailer’s website in the Netherlands. Kudos to Hema [here is their normal website] for letting customers in on a little fun.
Over the years I’ve done a lot of goofy things on our intranet (mirror-imaged the home page, turned the “staff”web into a disease-ridden “staph”web, etc.) but we’ve been pretty tame on the public side. Has your library website had fun?