Okay, so this isn't exactly a mechanical puzzle in the strictest sense of the word, but it is a clever object nonetheless.
This is the 6 Ring Burr Ball, which is an Impossible Object design from the prolific puzzle prototyper George Miller, and it was George's exchange puzzle at this years International Puzzle Party in Berlin (IPP31).
As the name suggests this is a ball, made up of six ring shaped pieces with burr-like connections between them. The pieces are all made from clear acrylic which has been laser cut into the ring shapes. The acrylic seems to be only around 1mm thick, but because of the inherent flexibility of the material it is surprisingly sturdy.
The puzzle aspect with this is to try and work out how the object itself was actually assembled. Because each of the pieces is interlocked into every other piece in opposing directions there seems to be no way of disassembling the puzzle without breaking one or more of the pieces in the process.
After much inspection and cogitation (guess work) I think that I have found a method in which this object could have been assembled, but I'm really not sure.
I saw this for sale on my last visit to Village Games in London, and as I have a bit of a new found soft spot for Impossible Objects, plus the fact that I love acrylic, there was no way that I could leave it behind.
It looks superb sitting on my table, and I really hope I get the chance to own some more of George Miller's acrylic puzzles in the future.