Security and Privacy are parallel tracks. Letting someone into your computer for purposes that you are not allowed to control, or even know about, is fraught with potential points of failure down the line. Do I, or you, need to know how or why right now? Is there always someone who is trying to exploit was to find hidden files to do something nefarious? Just allowing someone, anyone, to put 100k (the standard setting, not a limit) of info on your computer without asking, without allowing you to see what it actually does or says, is wrong.
CCleaner, FlashCookiesView and Flash Cookie Cleaner get good reviews. If you are using Firefox, you can use Foxit and flashblock, but remember, these files are ubiquitous – they are shared by all browsers on your system.
Here is the link for the settings manager at Adobe — feels like fox in the henhouse, and is not easy to use…
[Update: I just used a nice program from MacHacks named Flush.app – Flash Cookie Removal Tool For OS X. Quick to download and simple to use, for Mac users it seems a nice way to go.]