You pay for the library with your tax money...use it! My kids LOVE going to the library and we can spend endless hours there if I let them. Getting the books and movies from the library not only saves you money, but also clutter because when you finish reading a book you take it back!
We have gone to an envelope system again after several years of not doing so and have saved a great deal just by paying cash for everything we buy, including groceries. You really think about if you need it or want it when you are paying cash!