The best way to unleash creativity is to set as many restrictions as possible.
If I were to ask you to invent a new product, what would you create? How long would it take you? Could you even do it at all? Believe it or not, if I added a bunch of restrictions, chances are you not only could do it, but you'd do it in record time. That's because restrictions have the power to not only speed up the process, but deliver better results.