I haven't actually done the math, but this web site reports that this recipe works out to about 4 cents a load. A 5 gal batch will last me between 4 - 6 months (less during football season). It's good at removing sweaty, football smells too.
Magic Window Cleaner: No towel drying, no streaks, no spots! Fill an empty spray bottle with: 1 tablespoon liquid "Jet Dry" 3 tablespoons blue Dawn dish soap Fill to the top with water, shake. Spray your wet windows with the solution, scrub all over with a sponge, immediately wash off, that's it! by Titanium Taurus
Mom's Homemade Super Laundry Sauce One Single tablespoon does a whole load of wash! $1.76 for 128 loads of laundry? Safe for HE machines. ~ This makes 1/2 Gallon of concentrate ~ 1 bar Fels Naptha (Yes, the ENTIRE Bar!) 1 cup 20 Mule Team Borax 1 cup Arm Hammer Washing Soda (NOT BAKING SODA!!) 4 cups of hot water