NKW gave a nice summary of some recent actions. For more historical examples, I highly suggest any of James Bamford's excellent books on the NSA. _The Puzzle Pa

NKW gave a nice summary of some recent actions. For more historical examples, I highly suggest any of James Bamford's excellent books on the NSA. _The Puzzle Palace_ is a massive tomb, but a very good read. I haven't had a chance to read _Shadow Factory_ yet, but it is in my pile.