It would be even better if they could make the polygon shapes 'morph' - i.e., the points in the polygon should animate to their new locations... That would make it amazing!
There's a lot of cool stuff that you can do with some heavy programming. This site uses a neat trick to create random, 3d-like shapes based on your cursor position. As you move your cursor over the header, it redraws the polygons.
Animation can be a quite effective way of making your site stand-out. But it is very easy to overdo it: the animation can easily steal all the focus from your design, and make it less effective. So, when using animation, the trick is to usually try to make it subtle, as even a low level of emphasis will be enough. The Hero Banner of the Grav site is a good example of this.