windows - Is there no way to disable the storage of flash videos (FLV) in your temp folder?

I found out that even if you delete Flash cookies, the FLV files of all videos you watch are stored in a temp folder, typically C:\Users\YourName\AppData\Local\Temp. They are deleted when you close the video, but they are not securely deleted (overwritten). Is there some way to make this directory "virtual", so it is in-memory, or to stop flash from storing them there, or to ensure they are securely overwritten when deleted? Why does flash even need to do this when most people have 2+ Gigs of memory in their machines? Does any one have ideas about how to either stop these files from being written to disk or to ensure they are securely overwritten when deleted?

Thanks.