For some decades, a persistent bit of engineering vaporware has been the super-fast, super-cool carbon-based CPU. Researchers at Stanford have now managed a carbon nanotube CPU of comparable power to 1971’s Intel 4004.

Scaling it up poses a lot of challenges, so I wouldn’t call carbon’s ascendance inevitable, but getting vanishingly close to silicon’s limits in the next couple or three decades is inevitable, so alternatives are going to be a very hot research topic.