This puzzle was featured on my Print It Yourself video series: https://www.youtube.com/watch?v=ePinNtag72c
The 2x2 Chain is a twisty puzzle that links three 2x2 Rubik's Cube puzzles to create a very interesting challenge. The outer two 2x2s solve normally, but the inner 2x2 is subjected to a lot of external bandaging, making the solve very difficult. The puzzle is very easy to make, so I highly recommend you make it for yourself if you can.
You need three 24mm 2x2s. Print 2 bars and 20 extensions, and glue them on appropriately. You can position the bars however you want; to judge whether or not you want to use the same pattern, I recommend seeing how it turned out in the video linked above.