The WTFPL (Do What The Fuck You Want To Public License) is an uncommonly used, extremely permissive free software license, the March 2000 Version 1.0 was written by Banlu Kemiyatorn who used it for Window Maker artwork.[3] Samuel “Sam” Hocevar, a French programmer who was the Debian GNU/Linux project leader from 17 April 2007 to 16 April 2008 wrote version 2.0. It allows for redistribution and modification of the software under any terms—the licensee is encouraged to “do what the fuck [they] want to”. The license was approved as a GPL-compatible free software license by the Free Software Foundation. ~ Wikipedia ~

Isn’t that interesting? Here is the term of the license:

DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
Version 2, December 2004

Copyright (C) 2004 Sam Hocevar
14 rue de Plaisance, 75014 Paris, France
Everyone is permitted to copy and distribute verbatim or modified
copies of this license document, and changing it is allowed as long
as the name is changed.

DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION

0. You just DO WHAT THE FUCK YOU WANT TO.

In 2008′s April Fool day, Google changes all of the licenses on the SoC pages to all be WTFPL version 2. Here’s all of the Google’s fools for 2009.