I listen to an internet station in England, all-volunteer, that has a program host ("presenter," as the Brits call them) who pumps the station's stream into a flea-powered transmitter somewhere between 1400-1500 KHz to allow neighbors to enjoy the music without a computer or other streaming device. Several of the presenters are longtime radio amateurs and all have worked in commercial or community radio, so there's a bit of technical knowledge afoot there, but I have no idea if such a use is legal on the medium wave band in the UK.