Robert Chang, a Stanford ophthalmologist, normally stays busy prescribing drops and performing eye surgery. But a few years ago, he decided to jump on a hot new trend in his field: artificial intelligence. Doctors like Chang often rely on eye imaging to track the development of conditions like glaucoma.

Solar panels might seem like they're in direct competition with plants. One is catching sunlight to do photosynthesis, the other wants to take it to push electrons. Surely Highlander rules apply, and there can be only one on a plot of land, right? In reality, it's not a zero-sum game.