This depends on several factors.
1. If I am with a person of the opposite gender I put on Jupiter and Beyond the Infinite from 2001 and sync it to Echoes by Pink Floyd. This never fails to impress.
2. If I am with a person of the same gender I put on Ghostbusters and proceed to quote the film verbatim like an asshole.
3. If I am alone and still able to masturbate I will watch porn. I have disposed of my physical porn collection so I'd go with something on xhamster. Preferably POV.
4. If I am alone and unable to masturbate I will watch Aqua Teen Humger Force, which I actually have DVRd like a whole bunch of episodes so I don't need to put on DVD.