I’ve said on numerous occasions that personal finance and fitness share a lot of similarities. Watching what you eat isn’t that much different than watching what you spend, responsible caloric intake and responsible spending are quite similar, and lessons from one apply quite well to the other. Wealth Watchers: A Simple Program to Help You Spend Less and Save More  was written by someone who shows you the similarities because the author lived them.
Alice Wood, after a brain injury, found herself overweight and in significant debt, so she joined Weight Watchers. Through its program of diligent journaling and group accountability, she discovered ways to use those approaches to help her shed her debt. The Wealth Watchers  program is now a tour de force in the financial world, helping many get their finances on track.
The basic premise is that you have a Daily Disposable Income (DDI) that you can spend each time, similar to the points system of Weight Watchers. Through journals and active tracking, you can make sure that you don’t spend more than your DDI each day. There are other principals that build on it, like the Power of 365 (seeing the impact of one daily purchasing decision over a year), but the core idea is still about the DDI.
The second half of the book is basically a journal, which is valuable but I thought it wasn’t as useful to print out a small journal for half the book. Overall, I think the idea of a daily amount you can spend, both arriving to that number and then figuring out the impact of your decisions, can be very powerful if you find budgeting extremely difficult to maintain.