popa bar abba was the funniest character in the gemara I could think of at the time.
If I was picking now, I’d be Chanan bisha. He once slapped someone and was told by beis din to pay half of a certain coin. He pulled out a whole coin and asked his victim for change. The victim didn’t have the change, so Chanan bisha hit him again and gave him the whole thing.
I don’t have a gemara in front of me to cite the page.