w00w00 is a computer security think tank founded in 1996 and still active until the early 2000s. Although this group was not well known outside Information security circles, its participants have spawned more than a dozen IT companies. The two most famous examples are WhatsApp, the messaging service, and Napster, the pioneering file-sharing company.
Participants
The official website, explicitly states "there are no 'members'" only participants, which at one point included 30+ active participants and spanned 12 countries on five continents.
References
W00w00 Wikipedia(Text) CC BY-SA