Which TF2 character's voice lines are your favourite?

As the title says.
They don't necessarily have to be one of the nine classes, they can be anyone in the TF2 universe.
My personal favourite is the Sniper, especially the line when he gets a revenge kill on a Pyro: "Oooh, got ya right in the ovary."
Here's a reference page for the list of all responses of the nine classes.
Edit: I also love the Hoovy's a cappella of "Sandvich and Me Going to Kick Your Ass".
Edit II: I also like Pyro's line, "Mmmmmm mmm mmm mmmmm mm mmmm... mm mmmmm!"