Sphere is another in an increasing list of impressive student projects created in Unity. Here, a strong central idea is delivered through the medium of a first-person puzzle game with the most flimsy of narrative trappings. What’s clever here, as in so many of these playgrounds of spatial progression, is the mode of transport. Not portals, not cubes, but the titular sphere, a small, bouncing ball which chimes musically as it goes. Recall it with a click of the left mouse and the trail that it followed after being lobbed is marked on the screen; holding down the right button sends the player travelling along that same trail. Trailer below. Play online or download, for Mac or PC, here.