Wifibroadcast is a project aimed at the live transmission of HD video (and other) data using wifi radios. One prominent use case is to transmit camera images for a first person view (FPV) of remote controlled aircrafts.
In contrast to a normal wifi connection wifibroadcast tries to mimic the advantageous properties of an analog link (like graceful signal degradation, unidirectional data flow, no association between devices).