Pop-Up Magazine isn't something you page through on the train or scroll through on your phone. Every issue of the magazine is a live performance, one night only, bringing together documentarians, writers of all kinds, photographers, and radio folks for a 90-minute show. The issue "unfolds like a magazine," with short bits first and longer pieces following. Pop-Up doesn't record the show and they don't put anything online, so if you're not there, you've missed it. Next Wednesday, March 17, Pop-Up presents the first staging of their shorter between-issue series, Sidebar, in the atrium of the SFMOMA.