Alas, water pipes are much better for 1) noise and unintentional transmissions (which can be quite garbled and no one cares), and 2) low frequency transmissions (which can carry only low bandwidth communications). Trying to transmit meaningful communications at high data rates over water pipes would be a TREMENDOUS technical challenge, requiring a vast amount of signal processing to compensate for multipath reflections, impedance mismatches, thermal noise, pickup of an almost variety of interference soures ces, infinite variety of interference sources. , nonstationary channel characteristics, intermittent grounds, etc etc ad infinitum (or at least ad nauseam). Sorry about the cold water, I have seriously considered this scheme and believe that it can be used only for very short haul, very low bandwidth communications (say intra-building at 300 baud). , although that's a guess not a simulation result). ------------------------------------------------------------------------ Stuart W. Card, Consultant, Card & Associates -- Research & Development Box 153 RR 1 Newport Rd Utica NY 13502 315-735-1717 / FAX -8469 swc@uc1.ucsu.edu or cards@top.cis.syr.edu "Who is John Galt?"