He uses software magic to turn all images in Web pages upside-down. He also redirects links to http://www.kittenwars.com/. The guy behind that site send him an e-mail to him saying that he gets mail from people who think kittenwars has been hacked and demanding that he improve his security!
This is just plain delicious. The Wi-Fi owner could've just enabled WEP and the neighbors would never get the pass code. Instead he decided to have some fun with the bandwidth thieves. Bravo!
See http://www.ex-parrot.com/pete/upside-down-ternet.html for the full story.