Not that we've been searching for details, but reportedly in Colin Farrell's homemade sex tape, he turns the camera from his playmate, Nicole Narian, to focus on her cat. Each time an amateur porn tape surfaces, the unsympathetic shake their heads and say: "What were they thinking?" But this time we wonder: "What was the cat thinking?" And, perhaps more disturbing: "What do our pets think about our sex lives?" Man's best friend It's no mystery that pets are often present when humans feel the urge for romance. A 2003 American Animal Hospital Association Pet Owner survey found that 47...