Mark Matulaitis holds out his arms so the Parkinson's specialist can check his tremors. But this is no doctor's office: Matulaitis sits in his rural Maryland home as a neurologist a few hundred miles away examines him via the camera in his laptop. Welcome to the virtual house call, the latest twist on telemedicine. It's increasingly getting attention as a way to conveniently diagnose simple maladies, such as whether that runny nose and cough is a cold or the flu. One company even offers a smartphone app that lets tech-savvy consumers connect to a doctor for $49 a visit.