The Eccentricity of Kraftwerk

Mannequins, robots, and ringerless phones. From Wikipedia:

The band is notoriously reclusive; providing rare and enigmatic interviews, using life size mannequins and robots to conduct official photo shoots, refusing to accept mail and not allowing visitors at Kling Klang Studio. Another notable example of this eccentric behavior was reported to Johnny Marr of The Smiths by Karl Bartos, who explained that anyone trying to contact the band for collaboration would be told the studio telephone did not have a ringer, since during recording, the band did not like to hear any kind of noise pollution. Instead, callers were instructed to phone the studio precisely at a certain time, whereupon the phone would be answered by Ralf Hütter, despite never hearing the phone ring.