If it can, my advice is to save it in a file and look at it tomorrow morning. Chances are you'll want to make some changes to make it more clear and more polite. Personal Remarks Making derogatory remarks about others is a bad idea. Doing it behind their back is worse. Doing it in public is worse still.
Electronic messages are the last place for any kind of uncomplimentary remark.
Just don't do it. If you insist on posting a message or sending mail, make sure you do it the right way, use the correct mail class, and avoid spamming people. Read your company's mail policy. If you don't know, ask. Electronic mail is insecure.