Creative designers have given the annoying 404 Error message you get while navigating through the web a funny twist, just to lighten the mood. Maybe now there will be more happy surfers laughing when they get the error message instead of smashing their keyboards.
The North Face: http://www.thenorthface.com/404
Apartment Home Living: http://www.apartmenthomeliving.com/404.html
For a more comprehensive list: 35 Entertaining 404 Error Pages.