To avoid sleep- or drunk-posting, the following filter (borrowed from Google) will now be imposed...

Once a user has turned Mail Goggles on, Gmail pays attention to the time. If a user tries to send a message within designated hours — say, 10 p.m. to 3 a.m. on Friday and Saturday nights — a window pops up, requiring the solution of five simple math problems within 60 seconds before the message is dispatched. If a user can’t solve one set of problems, a new set is presented, accompanied by messages that gently scold, like “Water and bed for you. Or try again.”...

[The developer] said that while the program was conceived with drunken e-mailing in mind — the feature derives its name from the slang term “beer goggles,” a reference to impaired vision and judgment when under the influence of alcohol — it could also “prevent employees from sending an angry e-mail to a boss.”

http://www.nytimes.com/2009/01/11/business/11digi.html?em