Startup Idea : Customer Initiated Deal Website

I would like to see a site developed which allows users (us) to input the details of a business which they would like to offer them a deal. So your favorite local Pizza restaurant could be asked to sell vouchers for pizzas at 50% off. Once enough people register, the business is asked to participate in the deal. This way the deal comes from the users, not the business, and small local businesses can get in on the 'deal' act. Imagine a small restaurant getting 100 people saying they would pay $30 for a $50 meal. To participate in a deal could cost $1 to the user and nothing to the business. Suggestions?