What is the best way to protect INTELLECTUAL PROPERTY?

I have an idea for a website. But if I asked developers to help me develop it, don't it risk having the developer copy my idea!??!?!?!?!?!?!

I know this sounds ridiculous. But think about it. Facebook was created AFTER ConnectU. Facebook is NOT proprietary of an idea, and it can easily be mimicked.

I have a GREAT idea, but the technology is NOT proprietary. How do I protect it from CLONES?!?!?!? as soon as I launch my site, or ask developers or VCs to sponsor my IDEA.........