An anonymous reader writes "Researchers at Harvard University have developed a microfluidic device using ordinary paper and tape. Squares of paper are layered and connected with adhesive tape, channeling liquid horizontally and vertically in a very small area. Each square of paper has been treated with photoresist material, which creates channels that funnel liquid into tiny wells containing certain proteins or antibodies. The fluid interacts with that area of the paper and turns the well a certain color. It can, for example, detect varying concentrations of glucose. Lead researcher George Whitesides says such paper 'lab on a chip' tests may lead to a cost-effective, portable, and accurate method for diagnosing diseases in countries lacking reliable health care. The research appears in the current issue of the Proceedings of the National Academies of Science."