I read the above-linked article and used the Adobe Flash tool to remove flash cookies, which is linked to in the article. I found some Flash cookies from Tom Cruise's website, tomcruise.com, that had been stored without my consent. Read this excerpt from the linked article to appreciate the threat:
"What if there was a type of cookie that could:
* Stay on your computer for an unlimited amount of time
* Store 100 kb of data by default, with an unlimited max
* Couldn’t be deleted by your browser
* Send previous visit information and history, by default, without your permission"
I recommend using the tool and following the directions in this article. One of Tom Cruise's employees could compile your web browsing habits and pass those along to corporate scientology.