Of late I've been thinking of dreams. For me it's at least a mental space of internal perception where anything is possible (and certainly much more). Dream is as close as you can get to pure creativity.
As I embark on intellectual adventures in cognitive science, as I intend to, I begin with the basics. The first question I tackled, and one I'm often asked, is: "What is cognitive science?" It doesn't get much more basic than that.