1.  White vinegar
       
All-purpose cleaner: Fill a spray bottle with equal parts white vinegar and water (distilled is best), increasing the amount of vinegar for tougher jobs. Spray it anywhere that could use a good cleaning, but do not use this on marble surfaces.
Deodorizing your dishwasher: Add 1 cup of vinegar to the rinse cycle of your dishwasher. The vinegar smell will dissipate, de-stinkifying dishes in the process.
Garbage disposal cleaner: Freeze white vinegar in an ice cube tray and then run the cubes through the garbage disposal to deodorize and clean drains.
Clean your showerhead: Unscrew your showerhead, then place it in a plastic zip baggie filled with ½ to 1 cup of warm white vinegar. Let it sit for about 1 hour to remove mineral buildup. For showerheads that cannot be removed, secure the baggie onto the showerhead using a rubber band.

2.  Citrus

Soap scum and rust remover: Eliminate soap scum and rust from your shower by rubbing surfaces with the cut surface of a halved lemon. Let that sit for about a minute, and then use a scouring pad to finish the job.
Scented all-purpose cleaner: Add enough citrus peels to fill 1/2 of a large mason jar. Pour white vinegar over the top to fill the jar, and then place the lidded jar in a cool, dark place to infuse for at least two weeks. Strain the solution, pour it into a spray bottle, and use it as you would an all-purpose cleaner.
Fabric whitener: Add 1 cup of undiluted lemon juice to your laundry to whiten and brighten clothing.
Microwave cleaner: Add a few tablespoons of lemon juice to 1 cup of water in a microwavable bowl, then heat the mixture to boiling in the microwave. Let the steam penetrate the baked-on grime for around ten minutes before opening the door and giving the interior a good wipe.

3.  Baking Soda

Clear clogged drains: Toss a little baking soda down a clogged drain, chasing it with double the amount of white vinegar. Let it sit for a few minutes, then follow the fizzing mixture with boiling water. 
Oven cleaner: Coat the surface of your oven in a paste of baking soda and water, avoiding the heating elements. Allow it to sit overnight and then use a damp rag and a silicone spatula to remove as much paste as possible. Finish the task by spraying down the oven top with vinegar, then wiping with a rag once more. 
Hairbrush/comb cleaner: Coat hairbrushes and combs in a paste of baking soda and water to remove product buildup. 

4.  Borax

Insect deterrent: Keep creepy-crawlies at bay by mixing equal parts borax and sugar and strategically sprinkling it around the house. The boric acid in borax is poisonous to many insects, and it’s also said to be an effective rodent deterrent. 
Outdoor furniture cleaner: Prep your patio furniture for the season by spraying it down with a solution of 1 teaspoon of dish detergent, 1 teaspoon of borax, and 1 quart of warm water. Wipe and rinse. 
Pots and pans cleaner: Sprinkle borax onto a damp sponge, then use it to remove grease and baked-on messes from cookware. 

5.  Salt

Remove water stains from wood: Did someone forget to use a coaster? Remove water rings using a paste of salt and veggie oil. Let it sit for around an hour before buffing away with a rag. 
Cast-iron cookware cleaner: Clean your cast-iron cookware without affecting its seasoning by heating a bit of oil in the pot or pan, sprinkling in ¼ cup of salt, then using the paste to scrub away baked-on food. Remove the paste from the pot or pan using a paper towel. 
Clean copper, pewter and solid brass: Slice a lemon in half and sprinkle the cut surface with salt. Rub the lemon all over the metal being cleaned before rinsing thoroughly with water.