I did it last time I quit and I'm doing it this time.
Every day I put the money I would have spent on fags into my cash not ash jar (I actually use one of my old ashtrays!) I can then see how much money I'm saving. I have found a gorgeous pair of shoes I want that are Â£90 and I'm going to treat myself once I've saved enough
It really helps you to continue if you can see how much you spent on the damn fags and especially so if you have something in mind to save for!