Fnord666 sends this quote from an article at Slate:
"Despite the pervasiveness of law enforcement surveillance of digital communication, the FBI still has a difficult time monitoring Gmail, Google Voice, and Dropbox in real time. But that may change soon, because the bureau says it has made gaining more powers to wiretap all forms of Internet conversation and cloud storage a 'top priority' this year. ... a 1994 surveillance law called the Communications Assistance for Law Enforcement Act only allows the government to force Internet providers and phone companies to install surveillance equipment within their networks. But it doesn't cover email, cloud services, or online chat providers like Skype. Weissmann said that the FBI wants the power to mandate real-time surveillance of everything from Dropbox and online games ('the chat feature in Scrabble') to Gmail and Google Voice. 'Those communications are being used for criminal conversations,' he said."