Earlier quoted context omitted.
Google's employment onboarding makes this bit unambiguous. You are told from the outset that if you have any current side projects you need to declare them when hired. Google will then tell you whether you can continue them and still work there. You are also told that if you wish to start any side projects while at Google the online form to tell Google of your intentions is at such and such a link. After you submit s…
Doesn't California state law invalidate a lot of this? I signed non-competes that come with a little clause at the end: "pretty much none of this is enforceable in California. We have to say this because California is making us." Of course if you use company resources or IP you're out of luck.
As far as the side-project policy goes, as you say, you have to avoid using company time or equipment. But that's the easy part. The tough one, as nostrademons mentions, is the requirement that the project not be related to the company's R&D ("actual or demonstrably anticipated" I think is the phrase). In the case of Google, almost nothing involving computers will get by that clause.