30 Rock: "I want to go to there" and "working on my night cheese" any time I eat cheese.
Arrested Development: "What a fun, sexy time for you" as spoken by George Michael and "Hey, brother", which I'll say to almost anyone (I don't have a brother). Sometimes I'll switch it out with "Hey, possible nephew."
Parks & Rec: Whenever my roommate says anything in Spanish-- "If you ever speak to me in Spanish, please use the formal 'usted'." And I frequently do Jean-Ralphio's raps from "The Fight". "R to the O to the N N N. I say Swanson's got swagger the size of Big Ben clock." Also, anytime I'm at all sick-- "Everything hurts and I'm dying." And when I'm feeling lazy-- "I don't want to do things. I want to not do things."