This article caught my mind : 23 Things Not To Write in an Email. During the Lehman Brothers’ investigation, apparently, the examiners found suspicious emails by specifically searching for these 23 phrases:
So, just between us, be very careful when you include any of the phrases above in your highly confidential emails. The damage may be unsalvageable and you can get into serious trouble >.< . In fact, I think very sensitive issues should not be communicated via emails! That’s just so dumb.