InterPals - InterPals is a friendly community of over 5 million friends, language learners, travelers and penpals.
Meetup - Helps groups of people with shared interests plan events and facilitates off line group meetings in various localities around the world.
PenPal World - Connect with people all over the world
Event Hunt - Startups and Tech Events Curated By Locals
swap-bot - Swap-bot is a online service that organizes group swaps and a community of creative individuals.
Eventbrite - Discover Great Events or Create Your Own & Sell Tickets