Who are some famous people whose fates are uncertain? (It’s fine if there’s a pretty good idea what happened to them [airplane crash, died in Mexican civil war, etc.] as long as there was never a body or definite final account.) A few off the top of my head:
Amelia Earhart
Ambrose Bierce
Che Guevara
Butch Cassidy/Sundance Kid
Flight 19 (the five TBM Avengers lost in the Bermuda Triangle)
Martin Bormann was never found as memory serves, though most experts think he died in Berlin during the final days of the war (though Ladislas Farago swears to have seen him in South America). Mengele seems to be pretty well accounted for.
Raoul Wallenberg, although I assume he’s famous mostly because he disappeared; I assume there’s lots of people who endangered themselves trying to help people in the war who aren’t famous because we know what happened to them.
Did somebody already mention D.B. Cooper, also famous pretty much because he disappeared?
Glenn Miller. For years the official story was that his plane was lost in the fog over the English Channel; the Straight Dope ran a column about claims that he died in a French brothel and the potential scandal was hushed up; current belief is that he was a victim of friendly fire, his plane being accidentally downed by an RAF bomber.
Does being Prime Minister count as being famous? The then PM of Australia, Harold Holt, disappeared while swimming at a beach in 1967. He is presumed to have drowned, though he was a good swimmer, and his body has never been found. (Theories that he was taken away by a Chinese submarine have never been confirmed).