yeah, i think UU is mostly a US thing—the book has a pretty charmingly pithy description of it: "I could go into some detail about the theological and class differences between [Unitarianism and Universalism, pre-merger,] but suffice to say that Ralph Waldo Emerson was a Unitarian and P.T. Barnum a Universalist." and yeah totally agree that it's so hard to get a similar community structure without something church-shaped... UUs are probably the most successful one i know of that don't rely on any kind of belief, and they're a lovely thing to have. (quakerism in its modern form also doesn't generally require any belief, but they're a small bloc even compared to UUs, and also, their services don't have music, which is a bummer if you're there for music stuff :P)