Though I may decry the commercialization of holidays, I must admit that I do love giving and receiving gifts. But what if we could harness this energy, this spirit of generosity, this money that we spend on frenzied holiday shopping to collectively build something amazing? The answer is that people are already doing this, in the growing phenomenon known as crowdfunding.

Crowdfunding is the term used when many people collectively pool their money to fund something they believe in. In a sense,…