Team OS/2 was an advocacy group formed to promote IBM's OS/2 operating system. Originally internal to IBM with no formal IBM support, Team OS/2 successfully converted to a grassroots movement formally supported (but not directed) by IBM - consisting of well over ten thousand OS/2 enthusiasts both within and without IBM. It is one of the earliest examples of both an online viral phenomenon and a cause attracting supporters primarily through online communications.
The decline of Team OS/2 largely coincided with IBM's abandonment of OS/2 and the coinciding attacks orchestrated by Microsoft on OS/2, Team OS/2, and IBM's early attempts at online evangelism.