where good ideas come from

in his talk, steven johnson talks about where good ideas are born. he says that to create good ideas, there has to be a place where people from different walks of life with different experiences can come together and talk, like a coffee shop.
some ideas come from simple ideas during conversations (like the story of Guier and Weiffenbach who were talking about picking up signals from the newly launched Soviet satellite, which they succeeded in, and later on their invention becomes something now known as the GPS) and some ideas take a longer time to grow as they linger in your mind.
he also says that ideas should be shared rather than protected, since sharing them will result in more better solutions, because after all it isn't the idea that's important but it's how you execute it.