I'm not sure you can seperate a film from a developer. the same film responds really differently to different developers. I think the original question should be fave film+developer combo!

In which case .... I like to use FP4+ in my 4x5 LF camera. I rate at around 80 and dunk it in Rodinal 1-50 for 8 mins as my N-Process. But I also really like Efke 25 (rated at 25) in Rodinal too. It has a really nice vintage look to it.