Lots of ideas - almost overwhelming. Some are a little absurd - cigarette smoke to deter harmful plant insects? Some are much more practical, but unless you have those certain ingredients in your home (ammonia, castor oil, peanut butter, etc.), it wouldn't be worth running out to buy them. I tried the denture tablets in the toilet without any better results than a normal scrubbing.
This book has soooo many ideas for using grocery store items, that you can buy cheaply, to use in your garden to make all kinds of things, to keep bugs off your plants, or to help them grow.