Radioactive (DVD and Gimmick) by Drusko and Titanas
In this unusual effect, the performer writes a prediction and then asks a spectator to NAME ANY SONG. When the prediction is revealed, it is shown to be a radio frequency (like 92.4). The spectator can use ANY device (radio, cell phone, boombox, whatever...) and when she turns to that frequency, the station is playing the NAMED song. In any scenario, this unbelievable effect will eclipse all others. The selection is entirely free, and it works every time.
The DVD explains everything in great detail, and you are also supplied with special prerecordings that can reveal named playing cards and ESP symbols, as well as spooky noises for seance-themed routines.
Note that the song REALLY plays from their device: this is not a hidden recording box that plays a named song. The song is REALLY playing from the frequency you predict. Leave it to master creator Titanas to develop an organic yet modern miracle, like Radioactive.
"The custom modified gimmick connects to any sound device, we strongly recommend that you will use it with a smartphone in order to get the most out of the device."