well i dont know if these work aswell, and not 100% sure on the name, but pipe fish, which can be found on rocks at low tide, well near to where i fish anyway, are found in cod's stomachs alot. I only found out about when a mate told me that he had been out in a charter boat, fishing for cod, didnt catch a thing, so the skipper tried some pipe fish, and they started catching all off a sudden, and when gutted, the stomachs were full of them. Dont know if they work all the time, but if nothing else works, theres no harm in trying, never had any experience with them my self, so anyone out there is welcome to correct me