A m-thick PEE-PPy film is flipping and navigating over a 30°C moist paper. The transparent film labeled "PE" is a polyethylene film. The black film beside the PE film is a m-thick PPy film made from IPA/BFEE (7:3) electrolyte without PEE. This video relates to a paper that appeared in Jan. 11, 2013, issue of Science, published by AAAS. The paper, by M. Ma at Massachusetts Institute of Technology in Cambridge, MA, and colleagues was titled, "Bio-Inspired Polymer Composite Actuator and Generator Driven by Water Gradients."