Marshall and Lily have a tradition when they pick each other up at the airport, one wears a chauffeur hat and carries the sign while the other arrives with a six pack. Here's Lily with Aspen Yard's Ale.
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How I Met Your Mother Season 4 Episode 13 Quotes

Robin: I still say this is stupid. What happened to, "As we mature, the relationship matures with us?"
Marshall: That's just something Lily read in Psychology Today. Alright, she read it in Cosmo. Alright, I read it in Cosmo. Alright, it was CosmoGirl!

Lily [on the phone]: Hey, baby. It's lunchtime, and I love you.
Marshall [on phone in front of co-workers]: I reciprocate in principle, although with the caveat that there seems to be a bit of a surplus here on my end.
Lily: No, I love you more.
Marshall: Do we need to get in a room together and bang this thing out? (pause) Those sound like agreeable terms, although I may need to adjust my briefs