Every Saturday, I run a 12-hour sprint with 3-4 folks at the Quantbase office (30 Wall St, New York, NY) from about 10am to 10pm. The idea is to have a sort of “hackathon” without coding, to all put our full focus on something tangentially related to our work/career during the week. Some of the 12-hour sprints I've done in the past:
I do this every Saturday! Email me if you want to join this Saturday.