This is a Fortune 500 article about how careless email can take you down. Most of this makes common sense (not that typical users have any of that), but some of it is interesting. You might want to wake up to the fact that people performing investigations will look at threads based on the subject line – so if your discussion stops involving the business at hand and starts involving bondage, you’d best change that subject line. Again… common sense.
One thing that surprises me often when I read articles like this is the lack of mention about encryption. Email encryption, however, is still a little too advanced for many users to grasp I suppose. After all, you do have to trade keys back and forth or whatnot (unless you have a PKI infrastructure for your corporation, in which case you might as well not bother – if you’re going to go under investigation, they will be able to crack your email anyway).