One word: Royalties

This means you generate the idea and develop it enough to look interesting to a larger company who would be willing to pay you a royalty for your idea. This happens all the time. Rock stars, authors and scientists routinely license their creative ideas to other companies who pay them a royalty. Anyone can do it.

Your business, therefore, would be a think tank. You (and your team, if you have one) would consider the world's problems, see what kinds of companies are trying to solve those problems, and then develop compelling solutions that they can license from you.

You have to be able to sell your idea and develop a nice presentation, a little market research and an understanding of basic trademark and patent law.

The nice thing about doing this is that if you develop enough cool ideas you will have royalties coming in from a lot of different sources, this creates a stable, passive revenue stream that requires little or no work to maintain.

Start in your spare time and plan on the process taking 3-5 years. Set a goal to have a few products in the market that provide enough revenue (royalties) to cover your basic living expenses. Then you can quit your day job and dedicate more time and increase the momentum. A good idea business should have dozens, if not hundreds of license contracts generating royalties.

It's possible to pull this off. And it is a fun job (I'm speaking from experience).