Gil's link of the day!

http://chir.ag/stuff/sand/

This game is incredibly fun, but don't forget to turn off the namakujii at the bottom if you want to build stuff. He's a slug and will eat through walls and anything else!

One cool thing to do is to fill a big part with the spout, then make a plant web through it. If you burn the plant, water will drip down and more plant will grow, so it becomes and endless cycle!