SDAT
SDAT (or S-DAT) is a format of Digital Audio Tape developed by Sony. The "S" prefix denotes that it is the format which uses a stationary magnetic head. Shinji Ikari is seen throughout the Neon Genesis Evangelion TV Series and Movies listening to an SDAT player, noteably switching between tracks 25 and 26. Some has postulated that there is a possible connection between tracks 25 and 26 and the last 2 episodes of the TV Series. In Evangelion 2.0: You Can (Not) Advance, Shinji mentions that his SDAT player was given to him by his father, Gendo Ikari.