Meetup - Helps groups of people with shared interests plan events and facilitates off line group meetings in various localities around the world.
Four Hour Book Club - 300+ Books recommended on the Tim Ferriss Show 📚
Eventbrite - Discover Great Events or Create Your Own & Sell Tickets
Bookicious - Find the best new book to read with books collections for makers, founders and entrepreneurs.
Bigtent - BigTent is a web-based organization and communication portal for groups.
BookAuthority - BookAuthority collects the most recommended books on business, technology and science - as featured on CNN, Inc and Forbes