Cool Cousin - Shaking up the travel world with good old human connection
BookCrossing Core - Create own BookCrossing site based on Drupal CMS.
Nightly - One part dating, one part social, one part nightlife
Postcrossing - A postcard exchange project that invites everyone to send and receive postcards from random places in the world. For free!
Askfortask - On-demand App for pick up , cleaning, plumbing, handyman, moving and other tasks in your area
Linear - Streamlined issue tracking for software teams