Pocket FM uses Raspberry Pis to transmit radio in Syria
About two dozen small transmitters are being used to broadcast independent radio stations across parts of Syria.
Each Pocket FM box - powered by Raspberry Pi computers - picks up a satellite feed and re-broadcasts it on an FM frequency, so people in Syria can listen on ordinary radios.
The machines have a range of up to 6km (3.75 miles), which is often enough to cover an entire town.