This is simply amazing. Someone that goes only by the name of Voxel, has created a 3D version of the original Metroid game in Director! By taking the Metroid tileset, he built a utility that allows him to convert 2D sprites to 3D sprites, and then he uses those to build the levels of the game.
Another favorite of mine is this game by Squid S O U P. Snake delivers classic-style gameplay in a 3D Shockwave implementation. Very nice indeed.