There is a bar in Gramercy called Exchange Bar & Grill in which drink prices are set based on the current supply and demand of it’s patrons. It is a little complicated, but each order shifts the demand of a drink allowing for $0.25 price fluctuations every few minutes. So if everybody in the bar is ordering Run & Cokes, you may get a great deal on an Old Fashioned and vice versa. There is a stock ticker above the bar as well as a large ticker board that sows the current market price for each drink. Very cool.
Exchange Bar & Grill is located at 256 3rd Ave. in Gramercy, Manhattan.
Before you go, be sure to read up on tips about how to game a (drink price) market from this Wired article.