The efficient production of ethanol from low-cost biomass (e.g., corn, sugar beets, sugar cane, switchgrass and/or paper) has become increasingly important in making ethanol competitive with gasoline and decreasing the United States' dependence on foreign oil. For example, to reduce the cost of transporting biomass to ethanol production facilities, mobile systems for producing ethanol from biomass are provided. Also provided are small-scale ethanol production facilities. For example, instead of transporting biomass to the production facility, the facility is transported to the biomass or is located nearby the source of the biomass. The ethanol production facilities or components thereof may be transported via land, water, or air. Production of other products, such as hydrocarbons, natural gas, hydrogen gas, plastics, polymers, and proteins, can also be made by the methods and facilities. Any product described herein can be made in finished form or un-finished form and moved, e.g., to a fixed facility, e.g., f
