A Maglite 7D is even longer than a 7C. 
The most uncommon lights I have are by Peak LED Solutions. Not sure how collectible they are these days. But they make wonderful task lights.
The all steel CR123A has a momentary switch installed, but I’ve got the original tail cap core and post to convert back. 
The “Janus” double-head is a weird one. I put it to use only on one camp trip, which was pretty useful for illuminating opposing walls, but overall a lantern would do the trick. I’ve always wondered why Peak LED bothered to make it and can’t explain why I even bought it. 
Piston drive Nitecores (and the McGizmo, the super high end version of them).
Foursevens 18650 tube.
Sorry for the necromancing… 
Didn’t know in which topic put this light but I just want you to see it too.
Most expensive (and most extraordinary) 18350 light I’ve ever seen 
And who’d think these would be selling like a hot cakes… 15pcs in last 15 hours? (edit: selling numbers seem to be random )
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This is not collectable now but in 100 years I bet it will be.
Meote FM2 (not to be confused with Meote FM1)
Ugh I’ve never seen one even offered for sale anywhere ever.
djozz I hadn’t ever even heard of that one and now I want it… What have you done
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