I've been having fun trying to make shapes Greek style. This may be a bore for anyone already intimately familiar with the use of compass and straight edge. there are a few other things on there as well.

http://sciencevsmagic.net/

No, its the name of the website. Its got a cool game on it about geometry.

Its so fun when people only read the title and not the post. lol.

i dont understand how to play the geometry game.

You have to make a bunch of regular shapes using only straight lines and the intersections created by circles. If you make two circles, each from one of the original points, then you will create new points at the places where the circles intersect. From these points you can make more circles and lines creating further intersections. If you play around a bunch you can create all the shapes on the list. This will require a bit of thought, some of them aren't immediately obvious, but you can work out the ratios you need and then figure out how to create them using the relationships between different circles. You can also just make pretty patterns.