Is there not a way where an encryption engine cannot be developed that would protect from snoopers obtaining copies or signatures of your shared files?? In the same way as PGP Disk protects privacy. I am sure that just the title of a file is not enough to obtain conviction, some form of file ID must be required, if the file were encrypted then there could be no proof that you had a particular file within your shared folder. This may be pie in the sky but with a key server for public keys this may be a possibility in the future to help protect the innocent!!
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