Not me, but my friend, Roy. We were both poor grad students in San Francisco in the Sixties, and one day we wandered into a seedy pawn shop south of Market Street. He had a beat up Pentax H1a and I sported an equally worn Pentax H3v. Roy spotted a small black RF camera, dusty and very brassy, and asked how much. The shop owner, perhaps unaccustomed to the phrase, said, "I gotta be honest with you, it don't work. Frozen up or something. Fifty bucks and it's yours." I thought Roy was going to laugh, say "Yeah, right," and we'd be on our way. Instead, he fished around in his pocket and forked over the fifty bucks. I was stunned as I knew that must have been all the money he had. Turned out he knew what he was looking at. It was one of those Leicas made for the Luftwaffe and it had as I recall roller bearings or something similar to withstand the freezing temperatures at high altitudes.
Roy did a CLA on it, got it working properly, and sold it later on to a collector for what I considered a stunning sum (don't remember the dollar amount, but was a jaw-dropper).
I have never been so lucky.