I disapprove of assassination but I've got to admit this one scores 10/10 for sheer style.
Certainly the attempt to kill Castro, of all people, with an exploding cigar should rank higher. Just imagine how that CIA brain storming went: A: "We're tasked with killing Castro. Again. Any ideas? Anything? Nothing is stupid! Castro! Go! B: "Cigars" C: "Boom!" A: "I see we're in mind-melt here. No wonder the western world trusts us with their lives during these troubling times" If you insist on actually successful…
There were 600+ attempts on Castro: https://en.wikipedia.org/wiki/638_Ways_to_Kill_Castro
Granted, that's a figure from Cuban counterintelligence, so maybe slightly too high ;) But most of them are documented. And not only 'weird' ideas like exploding cigars - the last one, in 2000, involved 90kg of explosives: http://www.bbc.com/news/world-latin-america-38121583