Quote from Barney in No Pressure
Barney: Oh, this one looks interesting. [flashback to Marshall holding a video camera in his bedroom with Lily:] Marshall: Lily, I thought you said you wanted to. It was your idea. I starved myself for a week to get camera-ready. Lily: You had a bear claw for breakfast. Marshall: Yeah, a bear claw. Lily: I changed my mind. I just don't want Barney to see us doing it. Marshall: Barney is never gonna see this. Lily: Oh, come on. It's Barney. Eventually, somehow he's gonna see it. Marshall: Want to bet? [present:] Barney: So there really is a sex tape. [runs out]