119250 Question and Answer Script

Looking for an script similar to Yahoo Answers, [login to view URL] or ask.metafilter.com. Needs to be a social network driven question and answer script. I like this script a lot: [login to view URL] but it is only for Windows, ASP and SQL. I need linux, PHP and mysql. Script can be barebones and doesn't have to be pretty, I can do that. Just need to make sure it is template driven so I can change around the look and feel. Please provide examples of sites you built in bid. Looking to move fast on this project!