My mother has always been the ultimate recycler, decades before recycling and upcycling became fashionable.
My mother still decants oil from a large container into a clean dish detergent squirt bottle. The squirt nozzle is perfect for squirting oil onto salads, roasted vegetables and a saute pan. It keeps the oil contained and helps place the oil exactly where you want it. You can also use a sport-top water bottle for most of these uses, but the water bottles tend to be constructed of a thinner and less robust plastic, not intended for extended use.
Here are some other wonderful uses for a simple dish detergent bottle. Just make sure to mark the bottle with the contents and the date that it was prepared. You can print a squirt bottle label and adhere it to the bottle using glue stick. This can avoid any dangerous mixups:
Fill with water
Water plants exactly in the spots that you need
Refill pet water bowls
Use for cooking or soaking
Fill 2/3 with water and freeze overnight to use as ice packs. Once defrosted, use to clean hands, dirty picnic tables, etc.
Fill with oil for sauteing, salads and roasting
Fill with vinegar for salads and cleaning tasks
Fill with marinades, sauces and dips
Fill with pancake/waffle batter for perfect sized pancakes/waffles
Fill with egg batter for perfectly round omelets
Fill with shampoo, body wash and squirt just what you need
Rinse sudsy hair at bathtime
Use as squirt toys in the bathtub and/or pool
Store homemade bubbles
For small and portable size cleaning uses
Decant liquid laundry detergent easily
Store homemade stain cleaners
Store carpet stain remover and squirt just where you need it
Decant window cleaner from large bottles
Fill with diluted bleach for bath and shower floor cleanup and cleanup of outdoor furniture and toys.
For Crafts and Gardening
Squirt finger paint right where you want it
Decant school glue or modge-podge from large containers
Fill with liquid fertilizer and fertilize just where you need it