Seems like I remember some odd chatter about them using the chat areas in X-Box live or PlayStation or something like that too.
IIRC, terrorists used to do that for secret coded comms about future plans.
Yes also Gmail drafts. The idiots thought that because the email was never technically ‘sent’ it was safe. Not realizing that the draft they read and edits they made to it still were sent back and forth from their computer to the google servers over the internet and therefore were susceptible to interception by the NSA