Rabbah called Rav Amram "Tarda [Confused person -Rashi; Dribbling Idiot -Aruch]"; a beam in the Room split, and both claimed it was due to an affront to them: Bava Metzia 20b
Rav Amram challenged an analysis of Rabbi Sheshet, who responded, "Are you from Pumbedita, where they draw elephants from the eye of a needle?": Bava Metzia 38b
Rami bar Yechezkel sent a message to Rav Amram, "Tell me something from the fine things you cited from Rav Asi, regarding the [laws of] shelters built on boats": Eruvin 102a
Rav Amram saying, "Rav Sheshet taught us this lesson, and he enlightened our eyes from a Mishnah": Sotah 6a