Oscar nominee Paul Giamatti will play Santa in Warner Bros.' Vince Vaughn-fronted and currently untitled (née Fred Claus) comedy about the jolly one's black-sheep brother.... Brittany Snow and Kristin Cavalleri (Laguna Beach) have been cast as sisters in the indie thriller Fingerprints.... Saturday Night Live rookie Andy Samberg will play an accident-prone, Evel Knievel-worshipping daredevil in the comedy Hot Rod.