Low oil prices have led to $2 gasoline in some parts of the country, saving consumers billions already in 2015 -- but leading to massive layoffs in oil fields from North Dakota to Texas. 

Incredibly, the price of oil may not be done falling. The market is still oversupplied, the U.S. is still increasing production, and storage tanks are filling up fast. See the slideshow below for more on those and other reasons the price of oil may have further to fall.