Hell of Sand is a game that stretches the definition of “game” – there is no set of objectives, and the whole thing is more like a physics simulation than a game really. When I say physics simulation, keep in mind that I am talking about the kind of physics simulation you might actually see in a physics class, and not a Physx simulation.
I’ve pointed you toward the “pyro sand” variation of the game, my personal favorite. I think that within many human beings lurks a simple fascination with fire, perhaps some primal leftover from our early ancestors. This version of the game has several different settings for things that either are fire or can be set on fire – this is a way to sate your inner pyro without actually blowing anything up.
The most interesting bits of this “game” involve experimentation – what materials react with what other materials, what does this do if I place it next to this, et cetera. If you don’t think it sounds like fun, try it out – you’ll see quite a bit of time slip away before you even know it. For those interested in digging deeper, see also the second iteration of the “pyro sand” game.