where do ideas come from?

While appreciating any creative work, in literature, architecture, music, or even advertising, I'm always drawn into the creative process, even more than into the final work itself. It always fascinates me how people can come up with such wonderful ideas. One of the strategies that I find most interesting is the cross-pollination of ideas, the ability to transfer ideas from seemingly unrelated situations or categories.
I've watched Formula One races for ages, and have watched most ER episodes as well, and yet I could never have thought about this (via LunchoverIP). A team of doctors from a London hospital got in contact with Ferrari to learn more about their pit-stop preparation and team synchronization. And when you come to see it, it seems a pretty obvious comparison. Basically, you have a team of people waiting for somebody (or something) to arrive, both with the pressure of time to solve a problem. It could apply to a team of mechanics in a F-1 box or to a team of doctors in an operating room, and they could perfectly learn from each other. Brilliant!