I get the impression that a fair few converts to Eastern Orthodoxy are into extreme metal. I find this interesting, because I'm an extreme metal fan myself, despite opting for Catholicism.
I suppose metal fans feel at home with all those hirsute priests. Metal is of course very international these days, with fans listening to bands from all over the world. There are plenty of great black and death metal bands from Eastern Europe. Many of these bands draw heavily on Slavonic culture, so it shouldn't be surprising that Orthodoxy has an appeal for Christian metal fans.