> Multiple infinity puzzles can be combined to create a larger continuous puzzle. The image above shows some of the creative combinations possible with two infinity puzzles of different colors ($75, for two).
Nice! I haven't seen these before. There's also a brand of puzzles called Schmuzzles that are based on an escher lizard and tile. I would say the difference between these and our torus-based puzzles is that they employ a tessellation cut with repetitive piece shapes such that the image is guiding the construction (as all pieces fit in all places). In our puzzles, each piece only goes one place as they each have a unique shape. Our Klein Bottle and Cross-cap puzzles is are a new idea (to the best of my knowledge).
well if anything from the left side can be flipped 180 and attached to the right side of the klein puzzle you should be able to assemble two copies in the same configuration, then flip one whole puzzle over 180 and attach it to the side of the other.
EDIT: FWIW torus puzzles are definitely not a new thing - I had this one as a kid: http://img.tradera.net/images/096/270662096_95a37033-d8f9-4c...