When it comes to a humorous attitude to life and a general lightness of being, the Middle Ages are not exactly the first time period that springs to mind.
Enter: the "Goedendag". The Goedendag (literally: "Good day") was a Flemish weapon consisting of an iron pike and a club like bulge attached to a wooden shaft.
In a battle-style scenario, the person holding the Goedendag could be expected to have a pretty good day. The one on the receiving end, not so much...
While smacking people over the head with an iron club may in itself not be hilariously funny, it beats the Middle Ages second favorite pastime, witch hunting, by a mile.