If it's such a great idea, and you're such an altruist, then just post it publically. What's all the secrecy and coyly holding your cards close? Do you think they're going to sign NDAs with an "idea guy"? It's not the idea that matters, it's the execution, and if you're trying to run some kind of a hustle on them where you make any kind of profit or benefit, then it's going to be your execution.