29:08The talk features three startup office-hours discussions: a multiplayer game that teaches programming, a video platform for documenting daily progress, and Flexport, a software-enabled customs brokerage. Paul Graham and Sam Altman probe how each company attracts users, validates demand, chooses what to build next, and plans to make money. The discussions highlight practical lessons about starting with users’ actual knowledge, responding to early engagement, and learning from customers before committing to a business model. Flexport’s founder describes using software and licensed brokers to simplify import clearance, with a longer-term ambition to expand into logistics.