Big software companies don't just stick to software any more--they build computer chips. The latest proof comes from Amazon, which announced late Monday that its cloud computing division has created its own chips to power customers' websites and other services. The chips, dubbed Graviton, are built around the same technology that powers smartphones and tablets. That approach has been much discussed in the cloud industry but never tested at large scale. Amazon's surprise move echoes Google's effort to create its own chips to power artificial intelligence algorithms running in its data centers, which it also rents out to cloud customers.