I always found Chicken Boo sketches sad.
He was trying to fit into a world that didn't want him and the world always rejected him regardless of his actions.
I ran an NPC golden cat that could speak and cast spells like a cleric. It was interesting. The players actually liked having that character around.
I read some Greyhawk novels that featured a ranger, a pixie or sprite, a hellhound pelt, and a talking badger named Polk. The badger was originally human, but he was killed and reincarnated by druids into a badger. His character was amusing.
Those were by Paul Kidd. As I recall, they were White Plume Mountain, Descent into the Depths of the Earth, and Queen of the Demonweb Pits. There were also some short stories (and game stats) in Dragon.
I really liked those novels.