Historical ones

Art/Culture

• Algonquin Round Table
• Bauhaus
• Black Mountain College
• Blue Stocking Society
• Cacophony Society
• The court of Lorenzo de' Medici
• Geração de Orpheu
• The Inklings
• Lake Poets
• Merry Pranksters
• Oulipo
• The Stein Salon
• Villa Diodati
• Warhol's [Factory](https://en.wikipedia.org/wiki/The_Factory#:~:text=The Factory was Andy Warhol,47th Street%2C in Midtown Manhattan.&text=The Factory was revamped and,north end of Union Square.)

Business

• Lunar Society
• Paypal Mafia

Politics/Humanitarianism