If anyone wants to see how this could work with a company, check out http://zferral.kroud.co (this is in beta).
I've just build my own Questions and Answers app called Kroud. The idea is anyone can create their own 'Kroud' and start interacting with their customers through Q&A. I know the idea isn't original (GetSatifaction and Qhub), but I wanted to have a go myself. Let me know what you think of it. I've started one for Startups and added a few questions.