Upload & Sell: Off
I just got a SOOKY-M adapter for my 50 Summicron collapsible, and it's a pretty cool little gadget. It's basically a set of googles, similar to the dual range summicron, and it allows me to mount my collapsible (or the front section of a rigid, if you have one) in order to focus all the way down to around 16"-17".
Here's a quick test shot at about 16", just to get a vibe on it. This was at f4, and you might be able to see that the center is pretty sharp. I probably won't use it often, but it's a cool option to have for occasional short mfd work. I haven't tested the long end, yet, but I think it goes out to about 3 feet, so maybe the total range is around 16"-36"ish.