1. The landscape of thoughs, a reification of the domain of imaginary entities, memories, feelings, ideas, fears or any other object in the mind, seen together as making up metaphoric features: forests, jungles, deserts, rivers, valleys, cloudy mountains, etc.
2. To mindscape: as to landscape, the careful trimming/shaping of ideas, memories, or other mental objects, as when "mowing the lawn", "planting bushes", and/or maintenance on existing features in the mental world.
Marcel Proust strolled in his mindscapes, to bring us his books "In Search of Lost Time".
Used in reference to a person named Mike who uses Myspace all day long, even while he's at work. His love and obsession for Myspace is far too great for the mind to comprehend so an alternate universe is created and we call it Mikespace.