I started doodling with triangles one day and thought the patterns that emerged looked interesting. After some tweaking, I made the icon for this site using inspiration from that.

The first version made in Microsoft paint, the patterns and lines from this serve as the base for all the other versions.

An improved version made in in Adobe Illustrator, it uses a very similar series of shapes as before but the sections are filled differently.

Changing how the sections are filled again to make a 3d pyramid shape.

Adding lines instead of alternating how sections are filled.

None of the other designs worked well at a small size, so I simplified the previous two while still maintaining a 3D effect.