This paper discusses a novel microfluidic fuel cell concept that utilizes the occurrence of multi-stream laminar flow at the microscale to keep the fuel and oxidant streams separated yet in diffusional contact. The system consists of a Y-shaped microfluidic channel in which two liquid streams containing fuel and oxidant merge and continue to flow laminarly in parallel between two catalyst-covered electrodes on opposing walls without turbulent mixing. Preliminary results indicate that this novel fuel cell concept may lead to the development of efficient room temperature power sources of microscopic dimensions that are comparable or better in performance than conventional polymer-electrolyte-membrane based microfuel cells that typically operate between 60 and 80degreesC. (C) 2004 Elsevier B.V. All rights reserved.