Programmers, designers, QA types, and others in Southern California—or wherever! If you are an open-source enthusiast, then signup for the online Collaboration Tree Hackathon. Join in and collaborate on the open-source Collaboration Tree (cTree) web platform for community think tanks. You'll get to network and build your resume while working with like-minded techies to help advance the cTree project by helping create an open-source tool for online collaboration around specific topics or goals.