As to the issue of companies monitoring email. This is a very sensitive issue. I don't believe monitoring is right. If I receive a joke and print it then put it in 20 company envelops addressed to my friends and send them at my companies expense, I am in essence stealing from my company which is obviously wrong. However, the company does not have the right to open sealed US Mail.
Email is mail in non-print form.
It should only be opened by the recipient or automatically discarded if not deliverable or returned to the sender. But keep in mind your firm probably pays for your Internet connection. Probably paid for your computer. And presumably pays for your time. My mother is fond of saying never put anything in writing you wouldn't want to see on the front page of the newspaper.