The concept is simple: meet up with others in a cafe (hopefully one with plenty of power points), and write. The concept originated in the San Francisco Bay Area, amongst creative writers, but, thanks to social media, has spread amongst research students around the world. (See Thesis Whisperer for full description of goals, and the experience of actually using it for motivation.)
Their motto: "No critiquing, exercises, lectures, ego, competition or feeling guilty." Just show up and write.
Anyone is welcome to join. At the moment, it's an East Van coffee shop but anyone is welcome to propose other locations closer to your campus.