Paypal Mafia (13 founding team members of Paypal, met once every few months for year and helped each other to fund great companies)
Benjamin Franklin’s "Club of Mutual Improvement”, or “Junto” (maximum 12 people, meet weekly, the format is very similar to a mastermind group)
The Vagabonds (meet once a year, in the form of yearly road trips and campfire chats, from 1925 to 1924)
Members: Henry Ford, the automobile mogul, Harvey Firestone, founder of the Firestone Tire and Rubber Company, Warren G. Harding, US President, Thomas Edison, famed scientist and inventor, and Luther Burbank, respected agriculturist
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