Here are some common examples:

* Oil: Motor oil, vegetable oil, and mineral oil are common lubricants.

* Grease: A thick, semi-solid lubricant that provides a longer-lasting barrier between surfaces.

* Water: While not as effective as oils, water can be used as a lubricant in some applications.

* Synovial fluid: This fluid is naturally produced in our joints to lubricate them.

The effectiveness of a lubricant depends on its viscosity, chemical composition, and the surfaces it's being used on.