The entire episode "Just Say Yes" is full of snarky remarks. From "To be my brother you'd have to start out by being a member of the human race" to the conversation that Nick and Lisa have about toothpaste and the bathroom is rather hilarious.
Another of my favorite quotes is Connie's "BUILDING A BRIDGE! What does it look like I'm doing!?" from Mandy's Debut. So, it's your turn! What snarky/sarcastic/witty comments always make you smile?