It's what all actors try to do, really, to just preserve the child inside them because their imagination is quite available. I think partly it's because they're still making sense of the world. They haven't boxed everything up so neatly as most adults have. And the thing is adults haven't solved the world - they've just found a coping mechanism.
A Web site that promotes flow is like a gourmet meal. You start off with the appetizers, move on to the salads and entrees, and build toward dessert. Unfortunately, most sites are built like a cafeteria. You pick whatever you want. That sounds good at first, but soon it doesn't matter what you choose to do. Everything is bland and the same.