Purrs of contentment. Soulful eyes locked on yours over dinner. Valentine's Day? Not for pet owners. For those of us who share our lives with animals, this is a daily—if not exactly romantic—experience. So are the various barks, meows, whines, and other, sometimes adorable, often insistent, methods of communication our four-legged friends use to express what they want. Or how they feel when we don't get it.