Using wifi routers with basic wep to transmit video and audio signal. I did manage to link a DVD Player to a projector (over 300m line of sight) last year using two Draytek Vigor AP800's. I was thinking of a similar idea - but maybe adding something like a xibo installation, converting it from VGA to Composite AV and then sending it to various repeaters which would take the signal... and display it. The SparkLAN firmware inside would, I believe possibly support it... and allow for easy data transmission, without too much hassle! We did something similar with clever boffins from the Uni in Nov '10 and it was too good a list of kit to miss! back to the drawing board! Going to have to look for some other AP's....
Thankyou anyway though!