In returning from Burning Man this past year, I've discovered that there is a good amount of science involved in this whole thing. What whole thing, you may ask? Running a nightclub at Burning Man, of course. (Stay tuned to this space for more details on that.)
Let me give you a specific example.
You go up to Burning Man. Cars aren't allowed in Black Rock City, so you bring your old beater bicycle. It's survived this long, say fifteen years, so you figure it ought to be able to take the beating and keep on rolling. You have a blast out there, and when you come back, you don't remember much but you notice that all of your stuff, including the bicycle, is now covered in a talcum-powder-like dusty substance, which kind of stings the flesh if allowed to sit there for too long, and otherwise just gets *everywhere*.
This stuff is called "PLAYA DUST." It's a result of a dry lake bed, millions of years old, which once held prehistoric fish and other life. A ghost of the former lake still re-appears most winters in the form of a shallow pool of water in the middle of the Black Rock Desert. The chemistry of the lakebed tends towards the highly basic end of the pH spectrum.
The skin of our bodies tends towards the slightly acidic end of the pH spectrum. Therefore, that tingly feeling that you feel when you expose your flesh to excessive playa dust is actually your skin, reacting with the dust much the way that vinegar and baking soda fizz when mixed together. If allowed to persist, this reaction will result in injury. When this injury occurs on your foot, it is known as "playa foot" and can actually be quite painful and take months to heal.
Back to your bike. What I like to use to de-grease my chain is a combination of vinegar and citronella oil. Why? The vinegar is highly acidic, and the citronella oil contains two cleansers which are good at cutting grease: the alcohol that makes the oil burn, and the citronella, which is based on oils from orange peels which are widely known for their cleansing abilities. Combined, this mixture will leave all parts of your bicycle, including the chain, looking shiny and new post-playa.
But don't stop there. Go ahead and use this mixture to take the playa off of some of your other playafied objects, as well!