Microsoft outlook has a facility to "recall a message". However, despite what you may think it would do, all it does is send a message to all recipients stating that you'd like to recall the message. Basically, outlook has a "I was a dumbass" function. It just tells everyone that you sent the message to that you DON'T want them to read the message you just sent. WTF. So full of fail, only makes you go to read it more!