Flash Cookie, also known as LSO’s (local shared objects) and PIE (persistent identification element) can reveal what websites you have visited and offer unlimited user tracking to website owners.
Like ordinary tracking cookies, there is no option provided in your browser for deleting flash cookies. So you need a special tool. (I think the latest CCleaner is able to delete flash cookies).
FlashCookiesView is a small utility that displays the list of cookie files created by Flash component (Local Shared Object) in your Web browser. For each cookie file, the lower pane of FlashCookiesView displays the content of the file in readable format or as Hex dump.
You can also select one or more cookie files, and then copy them to the clipboard, save them to text/html/xml file or delete them.