This week on Car Talk, do birds aim their droppings? Ross in Seattle traded his green Acura for a white one, and suddenly he's scraping heaps of avian deposits off his roof. Elsewhere, Jenny's Sebring has a water retention problem in the driver's door, which is giving her mechanics a good laugh; Selene's about to kill her budding Hollywood career, and terrify her cat, by imitating the noises her Cadillac is making; and Dan has survived four years of driving in New York City, without Reverse. Has he earned a huge repair bill, on top of his spot in the Parallel Parking Hall of Fame? And, we know it's the season to be thankful, but why is a colonectal surgeon grateful to Tom and Ray for boosting his business? All that, and lots more, this week on Car Talk.