Vortex is a traditional puzzle-style game with some interesting use of Newtonian mechanics. As in many puzzlers, in each level you have to get from point A to point B. Here, however, you do not move the item directly, but instead place gravity wells and repulsors at various points in the screen, then hit the "start" button to see what impact they have on the item you need to move.
Backstory has it that the item is a ball of plasma, which cannot be manipulated directly, so you use the gravity and antigravity "vortices" to do so. But never mind that, we're in the realm of physics here.
The difficulty is that the tendency is to view placed objects as bouncers or reflectors, like the edge of a pool table, which would produce "angle of incidence opposite to angle of reflection" behavior, but since the objects are gravitational in nature, they do not behave this way. Instead, they evoke curved paths, which are harder to predict. It takes some thought and repeated tries to solve most puzzles. This is either interesting or frustrating, depending on your personality, I suppose.
It's a 2D game -- movement is confined to the plane -- but rendered in 3D, and visually well executed. Because of the handful of levels, it feels like not so much a full game as a sketch for a game, but it's well executed for what it is.