While we've covered what happened to Baby Azaria, etc, how about a discussion of our own personal most-likely-never-solved mysteries.
I had the same mailman for years and years (at 3 different addresses!), until I finally moved a couple of blocks away from his route.
Five or six years later, I was at the grocery store and ran into him. He told me that, a couple years ago, someone sent a huge envelope full of who-knows-what to my old address.
Of course, by the time my change of address form had long expired. He had no choice but to return it to the sender.
He went on and on about how "impressive" it was. Since it had been a couple years, he didn't recall anything about the postmark or return address, except that it looked "personal".
What was in it?
Who was it from?
Obviously the sender didn't know I moved, so why send me something all of a sudden? I only lived at that address for 18 months, so it would have to be someone from that time frame.
So many questions.