I have a friend who's been harbouring a reasonably good startup idea for the last 2 years. He's a solo-founder and is cautious in telling people his idea: perhaps he's told about five people all up. Personally, I believe he should take the opposite approach and pitch to anyone who will listen.
But it got me thinking: what is your philosophy for telling other people your startup idea(s)? Do you wait until a prototype is built? Or do you start pitching to everyone you meet from day one? Of course it differs from startup-to-startup, but it would be interesting to hear peoples experiences.
My personal belief is that people need to be force-fed anything that will require them to change a part of their life. And also: taking risks is an unavoidable part of being an entrepreneur. Thusly, I pitch every one of my ideas to anyone who will listen, prototype or no prototype.
I figure that my competition already hires people who are smarter and harder working than I am. The fact that I can compete at all means that either that nobody competent wants my market, or that the inefficiencies inherent to large organizations are larger than most people think. I suspect it's a little bit of both. Either way, I'm not going to waste my time keeping my ideas secret.
Expressing your ideas clearly has other benefits. The obvious is that you get some feedback before you put effort into development... but what is less obvious is that even if you fail, and /especially/ if someone steals your idea, clearly expressing an interesting idea (especially if you implement) looks good on the resume. Startups come and go, but you are going to have to sell yourself, likely, for the rest of your life.
On the other hand, as someone else in the thread said, "I'm a thousandaire!" which pretty accurately describes my current financial situation, so what right do I have to be giving advice?