Set Facebook and MySpace aside for a moment and consider another group of social networks.
It's the upper echelon of social networking with invite-only communities made up of movers and shakers, business leaders and high-society members with power and money.
Here's a VIP glimpse at three gated networks and how joining (once you're invited) can offer lucrative networking opportunities.
The community: Members range from entrepreneurs and business leaders to influencers in media, entertainment, fashion and sports.
More than 65 percent live in major European cities, and more than 10,000 are CEOs.
Behind closed doors: Aside from numerous marriages, business transactions and random acts of kindness among members, 14,000 events were posted by members last year, according to founder Erik Wachtmeister.