SPEAKER
SPEAKE(a)R: Turn Speakers to Microphones for Fun and Profit
(by Mordechai Guri, Yosef Solewicz, Andrey Daidakulov, Yuval Elovici)
Full Paper: http://cyber.bgu.ac.il/advanced-cyber/system/files/SPEAKEaR.pdf
Or https://arxiv.org/abs/1611.07350
Video: https://www.youtube.com/watch?v=ez3o8aIZCDM