Getting slightly offtopic in regards to SOPA/PIPA, a judge in the US ordered someone to provide the crypto keys and/or password so that police are able decrypt their personal computer in order to look for evidence...
http://news.cnet.com/8301-31921_3-5...icans-can-be-forced-to-decrypt-their-laptops/
So in the US at least (if the order gets through the appeals process), use of crypto to safe guard against police investigation is no longer a viable measure. (And I thought the 5th admendment was there to protect against this type of action, eg giving over evidence that may be used against you).
Mind you, if you're using our own personal computer to illegal activities, best to use external media to store your stuff... and hide it really, really well... The more they have to wade through, the more sloppy they'll be in finding stuff...