Text A Coder - Send a text, get a developer and project manager instantly
Meetup - Helps groups of people with shared interests plan events and facilitates off line group meetings in various localities around the world.
CodersClan for Trello - Outsource your code tasks directly from Trello
Eventbrite - Discover Great Events or Create Your Own & Sell Tickets
rysolv - Fix open source issues, get paid
Bigtent - BigTent is a web-based organization and communication portal for groups.