Subverted when Kallen is ruining Lelouch's awesome Batman moment in episode five because she keeps singing The Veronica's "Untouched". He tells her to be quiet.
Jeremiah: So this is how it ends. Well listen to me, you stupid idiots. I am undefeatable! You can never stop me! Death is only the beginning! Now if you'll excuse me, I'll see you in hell!
Kallen and Lelouche cornering Cornelia at the end of episode 13. After a kicking song, Lelouche simply points the gun at her and says: "You may want to buy a blender." After a while of absolute silence, Cornelia asks, confused, why she would want to buy one. Leloche cuts her off to finish: "So you can drink it all in." Also counts as being a Crowning Moment of Funny.
Sanji's revenge Evil Plan from the same episode is also of note.