It all started — it should be noted — with Steve Swink and Scott Anderson's Shadow Physics, revealed at the Game Developers Conference's Experimental Gameplay Sessions in 2009, and still in production at their upstart studio Enemy Airship (as yet offline, but already with this amazing logo designed by Phil Fish). After that came Lost in Shadow, Hudson's own upcoming fantasy/storybook platforming take on shadow-play.
And now, spotted very briefly at E3 in Sony's PlayStation Network reel, but now shining in a stronger light on their PlayStation.Blog, is echochrome ii, an upcoming downloadable that'll use the PlayStation Move motion controls as a flashlight to modify the game's cast shadows to solve yet more puzzle/platforming levels.
Sony's take does, to be fair, appear to be a logical next step from their original optical-illusion puzzler echochrome, but it is a curious case of Hundredth Monkey game design, and will be interesting to see how each makes its own mark as they all come to market.