Quote from Marshall in A Change of Heart
Ted: [on the phone] Robin! Hey. Hey, um, remember Scooby? Uh, well, he got out. Robin: "Got out"? What do you mean? Ted: He just walked out of the apartment. Someone must've left the door open. Marshall: [whispers] It wasn't me. Lily: Me neither. [gasps] He must've figured out how to open it himself. Ted: He's so smart. We should get him on Letterman doing tricks. Marshall: I know Paul Schaffer's sandwich guy. This could happen.