There are some steps you can take with regards to weight. How about using the money you're saving to join a gym? Find out if there are any healthy living initiatives in your area (these tend to be the more deprived areas) and you might get subsidised gym meberships or free swimming etc.
Or how about not buying any munchies because the hand-to-mouth action is a reinforced behaviour. If you think you probably take say 10 drags on each cig? That multiplied by 20 cigs a day means the behaviour is reinforced 200 times a day - what else do you do 200 times a day?!! The truth is its going to take a bit of time to get used to being a non-smoker and if you've got a packet of biccies there its going to be too easy to reach for them.
My last tip is to buy lots of fruit, not only is it good for you but as your sense of taste returns you'll enjoy it more than ever
