Note: I'm trying to avoid mixing Rav Chanina with Rabbi Chanina, but may not always succeed.
Traits and Conduct
He was a bachelor, and worked as a cobbler in a poor section of town, and yet never raised his eyes to look at the women whom he fitted for shoes; the local people used his name for their oaths: "By the lives of the holy Rabbis of Yisrael": Pesachim 113bAnecdotes involving other Sages
Rav Chanina coiled up his Tzitzit-Fringes before giving the garment to the launderer, out of concern that they might be cut accidentally, and replaced with improperly dyed strings: Menachot 41b
Rav Chanina [Kara] reported a law in front of Rabbi Yannai. Rabbi Yannai told him to say it outside; the ruling is incorrect: Ketuvot 56a