There's plenty of room on an 802.11 or "wi-fi" network for simultaneous transmission of multiple mp3s. So, mp3 players should transmit a weak signal of some selected music as a stream of mp3 packets, each one identified with a unique id for that player. Then, on a crowded commuter train, you will have the option of listening to your music on your mp3 player or 'tuning in' to one of the packet streams coming from one of the dozens of mp3 players in your train carriage.Watching who else rescans for a new source as the person whose player you were listening to gets off the train could be interesting.A downside to this idea is that you may just discover that everyone is listening to rubbish, but you'll at least have your own mp3s still.-- hippo, Apr 25 2005 iPod pirate radio http://www.engadget...y/3597373383872462/the how-to guide [tokyofist, Apr 25 2005] i believe that this is already being done with modded fm transmitters (i guess wireless could work too). see link.-- tokyofist, Apr 25 2005 I would rather keep my battery life for me and not for strangers on the train.-- Giblet, Apr 25 2005 random, halfbakery