Have you ever faced a situation where a link you clicked on led to a bland "Page not found" error? Yes? Well, here are some funny variations of the same.
http://www.dailymotion.com/404.php
http://home.disney.go.com/error/pagenotfound
http://www.homestarrunner.com/404
http://www.homestarrunner.com/systemisdown.html
http://www.craigslist.org/404/
http://www.happycog.com/404 (I liked this one particularly)
http://www.pen-and-paper.de/404.php
http://www.galiacho.es/404 The blue screen on this page reminded me of something almost everyone has seen at some point of time (if you're a Windows user, that is).
http://www.martinkorner.co.uk/404
http://www.nextwaveperformance.com/404 This one has a cute flowchart that is, well, funny! :-)
http://www.porcupine.gr/404 This page is somewhat thoughtful, and slightly philosophical.
http://kottke.org/404 This one has a frank headline!