Great idea for a post and an important topic. A somewhat similar topic came up at our recent Chicago meetup, when someone who saw our sign came up to us to ask us what Less Wrong referred to. We didn't necessarily have a great answer at the ready besides relaying some of the basics (website/group blog about rationality and thinking better, etc.). We spent a few minutes afterward talking about what information a good LW elevator speech might include. We didn't want it to sound too stilted/formal, e.g., "refining the art of human rationality" from the banner at the top doesn't sound that inviting in casual conversation. Does anyone have approaches that have worked?