I use Lucas Pawpaw ointment. It's designed to be multipurpose but it does a very good job at moisturising lips and it's also cheap and you get a lot of it. I'm pretty sure it's an Australian thing though so most of you probably haven't heard of it.
I also quite like my cocoa butter lip balm. The labels badly scratched though so I can't make out the exact brand name.
I used to use carmex but apparently it makes your lips more dry in the long run so you keep buying more. I've also tried lanolips which is quite expensive and meant to be really good but it did pretty much nothing for me, unfortunately
