The Countmobile

From Muppet Wiki

The Countmobile is the car owned by Count von Count; the vehicle was featured prominently in Follow That Bird. A near antique, bearing some resemblance to a Stanley Steamer, the Countmobile is painted purple and boasts bat-like wing appendages. The New York City license plate number reads "12345678910."

The car has also appeared in the book Count All the Way to Sesame Street and The Sesame Street People in Your Neighborhood 1991 Calendar.