How about chatting online about marijuana cultivation? Can one be guilty by association? How worried do you need to be about the government accessing this kind of information about you? These are not the questions of the pot-paranoid, but are sensible to consider, and not easily answered.
Owning a magazine subscription alone is not (yet) an illegal act and may not even draw attention. Online activities is fraught with danger. Chatting online about herb is not illegal, but talking about growing or buying herb might be. The degree to which government search engines such as Carnivore are examining cyberspace discussions remains in question. The hunt for child pornography shows us that the technology is in place and the operators are trained to use it effectively to find their target. If you are engaged in illegal activities that are apparent from internet forum chat, IRQ discussions, or non-encrypted email, you have a lot of reason to be worried. And this was the state of affairs before the Homeland Security Act. Only a fool would assume that there is anything such as electronic privacy today, and if the BCF (Bush Crime Family) prevails in November, it may well be that they choose to broaden the focus of these intrusive and devastating techniques to drugs.
Addition websites on government search engines: