I'm currently investigating the different locations where the flashplayer in OSX stores its files.

The reason is protecting privacy. I've found that Chrome and Firefox both read/write to the following directories:

~/Library/Caches/Adobe/Flash Player/AFCache
~/Library/Caches/Adobe/Flash Player/AssetCache
~/Library/Preferences/Macromedia/Flash Player/#SharedObjects
~/Library/Preferences/Macromedia/Flash Player/macromedia.com/support/flashplayer/sys

The last two directories are locations where Firefox stores LSO cookies for long time tracking. You can manually delete them yourself or do this automatically using an extension such as BetterPrivacy for Firefox.

However, I have no clue to what the AFCache and AssetCache are for. I assume that you should not delete them as cache generally improves the browsing experience, but I'd really like to know what is stored there?

I've been searching the Internet quite a bit now, but there does not seem to be much documentation.