Some of us are mental patients at making sure our computers are clean of the cookies http://www.howstuffworks.com/cookie.htm that websites like to deposit on them without our permission to track us.  I use the free program CCleaner http://www.filehippo.com/download_ccleaner/ to clean my computer. While those days of being able to clean them out ourselves are about to come to a close. Meet "Ever Cookie."

"Using eight different techniques and locations, a 'security' guy has developed a cookie that is very, very hard to delete. If just one copy of the cookie remains, the other locations are rebuilt. My favorite storage location is in 'RGB values of auto-generated, force-cached PNGs using HTML5 Canvas tag to read pixels (cookies) back out' — awesome."