The Awesome Power of Spare Cycles, Chris Anderson explains how Open Source, You Tube, and My Space are all powered by spare cycles. In reality all of society from art, music, and literature all the way to science and politics are built on spare cycles.
In your high school or college sociology class you might have learned that societies are created on the surplus food that a group of humans can create. In other words you don't get tributes to Zeus until there is a surplus of food lying around that the peasants won't mind parting with. The arts, religion, politics, and kingdoms all come from the ready supply of extra food.
If you want more open source, then create an environment where more people can take the risk of creating open source projects and even potentially waste their time on them. Consider that most projects fail. Most projects do not become popular. There must be enough surplus developer time to support those risks so that the one lucky project that changes everything has the chance to get created and have a few people waste their time on it before it becomes a product.
My company has taken a risk on me. They believe that the can sink me and some capital investment into my projects and I will create a return on the order of millions of dollars. I'm going to have to go out and make that expectation come true... yet at the same time I need to have permission to fail a few times. If I can't afford to fail... I can't afford to take the big risk that will pay off.