After the previous, more specific challenge, the next one was back to wide-open. The idea was simply "hand-drawn," with a minimum of digital manipulation. I didn't want to hassle with actually drawing something and scanning it in, so I just used SketchBook Pro again to make it look fairly hand-drawn.
This design is based on what I can see sitting here on my couch. There are some overlapping segments of a baby gate which form a rounded grid, and the colors are based on the back yard behind me (tall hedges, stone retaining wall, some flowers).
The shapes didn't come out exactly like I wanted - the points of the leaf shapes don't quite line up right to balance the negative & positive space. I lost sight of that when I was trying to get the overall repeat to look right. I decided to leave it, since I would have had to redo almost the whole thing to fix it. A lesson for future designs!
There were a couple of different polyhedron/crystal entries I liked: a purple one, another of jewels, and one of salt. I also really liked these raindrops.
My entry came in 160 out of 500, with 95 votes.