This is the latest revision of the TuneCast FM transmitter. This is a universal FM transmitter that plugs into the standard 3.5mm headphone jack and will transmit the audio through a FM frequency range between 88.1MHz and 107.9MHz. The TuneCast 3 has a 20-hour battery life or can plug in directly to a power source. It will be available in November for $50.
Press Release [Belkin]