Most bloggers who write about saving money don't go nearly far enough. The REAL secret to saving money is by buying less stuff.
For example, you can save money on books by buying them used on eBay instead of paying full price or close to it at your local Barnes and Noble. But you can save even more money by using the public library. You can read just about any book that's ever been written at your local library, because if they don't have the book in their collection, chances are they can get it for you using a service called inter-library loan.
You can save money watching television by shopping around for the best deals on cable or dish television. But you could save even more money by giving up television altogether. That's a more radical lifestyle shift, but it's going to save you way more money, and you'll be healthier, mentally and physically. That time you used to spend in front of the tv could be spent with friends playing board games or card games and socializing. Or it could be spent exercising.
You could save money on a car by buying a used car instead of a new car, sure. But you could save even more money by redesigning your lifestyle so that you no longer drive a car. You might have to move closer to work or get a different job. You might start riding a bike or walking. But you'll save a fortune, and the health benefits from all that exercise will make you live longer too.
So when you're thinking of ways to save money, don't be afraid to get radical about some stuff. Eliminate the things you used to buy, and you won't have to worry about saving 20% here and 30% there. You can save 100% of the cost of a wide variety of things.
