Jigsaw puzzles are terrible. They tap into our subconscious desire to complete tasks even if they are pointless, the reusability is minimal, and they offer next to nothing for the creative or just inquisitive mind.
When in one of my former lives I needed a creative activity for young children that would encourage them to view themselves as part of a group, I designed the anti-puzzle above. It consists of only one piece, which is blank. Each child would receive a large printout of the tile, cut it out, decorate it with something personal, and put it on the wall.
There is no difficulty putting the pieces together. Everything fits, and you cannot make mistakes. The only choices that are left are the designs of the individual pieces, and the place on the wall. I can imagine grownups could use these for brainstorming, post-it style.
In a later part of that life, I recycled the idea for older children. Here, there are three different snowflake shaped jigsaw pieces (which I had cut out in large numbers and many colors using a die cutter). This turned out to be surprisingly difficult, because the pieces appear to allow you some choices. However, if you want to fill larger regions without gaps, it will always look like this:
The hexagonal lattice is something our squared brains have a hard time to adjust to, apparently. Still, choices can be made by selecting the colors and shape of the design.