Shopping trips become protracted. Friends and family call, wondering if you've been abducted. But it's a compulsion car enthusiasts can't help. Always on the lookout for interesting and exciting cars, any random parking lot can turn into a smorgasbord of "I haven't seen one of those in years!" You stand there taking smartphone pics of random old cars, confusing passers-by as you text and tweet your finds with a goofy smile on your face.