Ask HN: Kickstarter for Startups?

What would you think if a site existed that was basicaly a kickstarter but for startups/for-profit businesses.

So a startup or concept would come on and post their idea and the community would then buy shares/equity into the company?

I was thinking that because actual profit can be skewed so much, in exchange for buying equity/shares, the startup would payout a percent of revenue back to the investors. That way it couldn't be up for debate what that number is. Thoughts?