Triangles and hexagons. Take two.

Using yellow hexagons, green, blue and yellow triangles, very little color manipulation.

Blue hexagons, green and yellow triangles, lots of color manipulation.

Both triangles and hexagons in green and black only.

I like this one. I shrunk it down with the idea it could be a logo. There are only two sizes of triangles here, but the large aquamarine have a little bit of an optical illusion going on, with some looking smaller and others larger.