New one to watch out for: you get a 'Daemon' notice about a failed email, which was interesting because from this particular machine I only sent one email and I got a reply but I had two Daemon notices.
Interestingly, my company's spam filter tagged it as spam, not sure what it saw to recognize it as spam, but the supposed email I sent out had stuff in the main message and with a bunch of HTML code, something about a credit card and needing verification, pretty big hint right there, but of course I never sent anything like that. Just something else to watch out for. This came to my workplace, not my home, so don't know if there is some kind of commercial targeting going on or just coincidence.