GNOG is a cute little puzzle game in which you are left to click and poke around without any instructions and without knowing what your goal is. This is a little frustrating at first, but once you realize that you are trying to open up the big cartoon heads, things start to make sense. Or as much sense as opening up floating heads makes.
There are some common tactics: right-click to flip the box, figure out how to pop the back open, then things get weird after that. The main draw here is the surreal art and soothing music. It's not that hard and it really just feels like a point and click adventure with no story. The game does get some negative marks for crashing on the end puzzle (with no way to get there without starting over) and for not working if you have Citrix receiver installed on your PC. Talk about weird.