Ask HN: How do you protect your idea?

Since Hacker News is, in my opinion, the best community of businessmen and hackers, I have come seeking advice.

I have a website that I would like to release to the wild soon, but I don't know if there are any legal precautions I need to to take before I launch (do I need copyright, patent, etc.). What steps should I take to make sure that my idea is protected?

I'm asking for advice and/or pointers to any literature which I can read about the topic.

Thanks