Eons ago - when my now teenage son was an adorable little boy* - I was away on a brief work trip. I promised this appealing little squirt of humanity a present on my return, and said that he could choose what it might be. Fully expecting him to ask for a pet tiger or a helicopter or the like - I was delighted when (in fewer words) he said that the sole thing his heart ached for was "a wind up beetle".
It took a very long march around pretty well every toyshop in a pismire provincial town before I finally found what I thought was perfect: a wee beetle which when wound up scuttled across the floor quite convincingly.
Rather sweetly, on delivery he nearly cried with delight. I'm unsure of exactly what the appeal was, perhaps the unfathomable mechanical intricacy - for such a cheap mass produced thing it did have a certain magic.
The toy remained in his collection of small boy treasures for a long time - inevitably it eventually disappeared - probably into the bowels of a the natural enemy of the wind-up beetle - a vacuum cleaner.
I am unable to find a picture of long lost beetle, but I can find a nerdy video of one of these:
It's a Curta mechanical calculator. So delicate, intricate and complex that they too are magic. My big boy heart aches for one. Easily found on ebay the only problem is that they are insanely expensive for what would really be a desk ornament.
You could be sure that I wouldn't lose it to a vacuum cleaner though.
* I still adore you mate, but if you have a beer in front of the telly then, as repeatedly asked, please do not leave the frigging bottle clattering around the sitting room. Jesus.
Oh - and you might warn me should you take the last one.