Sample of a fun renderer. We made these in my Grade 6 art class and I've always enjoyed them.
What I didn't realize at the time is they make an interesting graph. Assuming you have two domains of equal size, you can start at the top/left and work your way around the entire outer boundary counting off tick marks. Given a set of X/Y coordinates, you can map the intersection of any two domains.
It looks cool, but I'm not sure it communicates anything meaningfully.