The Adobe Flash Player maintains proprietary cookies called Local Shared Objects or LSO’s. LSO’s are capable of storing 100 kb’s of information for an indefinite amount of time by default. When you clear your browser history in Internet Explorer, Firefox or Opera on Windows, Linux, or OS X LSO’s are not cleared from Adobe’s local repository. In fact, all the information in those cookies will remain indefinitely until they’re removed by the issuing website, or by you via a cumbersome and ridiculous process. Unfortunately, I haven’t even explained the worst of it.