Pretty funny and unfortunate for those that mistakenly publish a private message to the world. Looks like some people are purposely posting to get on DMFail now though.

 If you are the kind of person who can’t help but look when you drive by an accident scene, DMFail is for you. The site, which has been all the rage on Twitter for the last few days, shows direct (private) messages that were sent improperly on Twitter and are therefore public.

 

If you want to send another Twitter user a message that only she or he sees, you type [D + username + message]. But a lot of people accidentally type DM (for Direct Message) instead of D, and when that happens you pay the price of having your message pop into your Twitter stream for everyone to see.

 

DMFail grabs all those messages and reprints them on its site for everyone to see, which can be quite a horrible experience for the people involved. Thus the accident scene analogy.

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http://www.techcrunch.com/2008/12/28/dmfail-another-reason-to-just-not-send-private-messages-on-twitter/