Anything the guards say, anything Sheogorath says. But my favorite follows through every TES game. "The best techniques are passed on by the survivors." ~ Gaiden Shinji, the first Blademaster. Even the first TES game, Arena, that quote was there.

From Erandur: 'Feel the benevolence of Mara!' 

While smashing people to bits with his mace. 

I haven't heard every quote from all of the games obviously, but this one has always been my fave.

"I fight for the men I've held in my arms, dying on foreign soil! I fight for their wives and children, whose names I heard whispered in their last breath. I fight for we few who did come home, only to find our country full of strangers wearing familiar faces. I fight for my people impoverished to pay the debts of an Empire too weak to rule them, yet brands them criminals for wanting to rule themselves! I fight so that all the fighting I've already done hasn't been for nothing! I fight... because I must."
―Ulfric Stormcloak

that, and anything that comes out of Shegorath's mouth tbh XD