The stars got fancied up and dressed down to film their latest projects this week. Josh Duhamel sported a tux (with bow tie!) on the set of Garry Marshall's New Year's Eve, while Leonardo DiCaprio kept it uber casual wearing pajamas for his J. Edgar biopic. Meanwhile on the set of Cougar Town, Courteney Cox accessorized with a cane (she's still recovering from a recent knee surgery). Check out all of the famous faces in this week's stars on the set!