This three month-old shop took the seven of us by surprise.    With great lights and windows, the latter possibly reclaimed, a definitely reclaimed barn door, bright yellow stool seats made out of wood stumps, brightly colored striped murals, a lending library, and a playful ambiance throughout, we felt we were in the midst of a great hangout discovery.  We wondered how they ever inlaid the wooden strips into their concrete tables, and then covered such diverse topics as the amazing formula for Roman concrete being lost for several centuries, modern insulation materials vs. past ones, the governance situation of our friends new co-housing development and why some such communities thrive while others struggle, and the changing  relationship of Teddy Roosevelt and William Howard Taft.    7530 N. Willamette