Seems like a good technique is using a remote server in a country like Russia, with SSHFS over Tor, and a virtual machine. All of the files are stored remotely but you have access to them as if they were on your actual machine, plus they are encrypted on the remote server, plus you cannot be linked to the remote server. Persistence and nothing for the piggies to demand you decrypt, unless of course they trace your connection to the remote server and get the Russians to demand that you cooperate (which in this case they wouldn't do, since CP is totally legal to possess in Russia anyway). I wonder if the pigs in the UK think that they can demand you to decrypt a filesystem in Russia.