The scandal surrounding the affair and subsequent resignation of David Petraeus has also exposed the ability of the FBI to track and read our electronic communications.  For an in-depth analysis on how this is done,  I highly recommend reading yesterday's blog by Chris Soghoain at the ACLU Blog of Rights.  Chris is a Senior Policy Analyst with the ACLU Privacy and Technology Project and he breaks down the methods the FBI can snoop email even when taking steps to avoid detection (as Petraeus tried to do). 

It's high time we modernize our privacy laws—by passing this proposal that is now before the Senate Judiciary Committee—to protect our digital communications.