MSN (ConceptTopic, 15)

From Compile Worlds

MSN short for Microsoft news ads Network, was a instant messaging protocol and network combination that ran a variety of services, most noticeably the Windows Live Messenger client, which everyone just called MSN anyway. In 2012 Microsoft announced it was discontinuing MSN in favor of supporting Skype, since anyone who actually used it had already got a Skype account or went on TIMP anyway. In March, MSN will officially be dead.

It isn't too sad though, the official client was becoming a resource whoring ad fest anyway, and the protocol was the most unreliable out of the Big Three (AIM, YIM, MSN).