The current study addresses the development of a flexible microbial fuel cell (MFC) in a tubular configuration. Nafion tubing is employed as a one-compartment MFC and is used as the membrane and the main body of the system. We use an ultra-flexible carbon sleeve as electrode material for both the anode and cathode; the anode is placed inside the tubular membrane, and the cathode is wrapped on the outside of the membrane. We illustrate how, using both the membrane and the new electrodes, there is increase the power density of the system, which is shown to work successfully with human urine as the fuel. We also show how the covering of the outer surface, that is, the cathode, by means of a waterproof and breathable plaster strip, maintains the high output levels without the need for hydration.