Ever since my first days with Minox in my pocket, I tried to devise ways of keeping it secure. I had an LX once, which took a tumble onto the pavement. I believe this was during the late 90's. Sadly, it had to be send to repair (actually, this is how I came to know Don Goldberg of DagCamera). My first attempt was naturally, to employ the button tab at the end of the chain. That was a good idea but it meant that I had to wear a jacket and that jacket had to have buttons. I had none, so that plan failed.
Then I adapted a lanyard, taken from my company id card and fashioned it into a neck-type of thingy, and wore my Minox hanging on my chest. That was good, but I also had a Minox meter hanging by a similar lanyard, and when I was leaning forward for some reason, the two dangled and knocked each other. That method had to go, and the belt case went its way too (you need a belt for it, and I wore tracksuits almost at all times).
And then one day I attached my camera on the key ring, I do not remember why. Anyways, that gave me an idea, and I used a shorter chain, attached to the camera locking bush at one end, and had a large key ring at the other. When i was shooting, I was slipping the ring around my pinky and kept the camera secure and if it slipped my hand, then it would still remain attached to me.