I don't listen to them, but my friend does (come to think of it, my friend does practically everything...)

I like them, but I can't appreciate music with that much volume, nor am I too much of a fan of German... I think they're good, just not my style ^^

I do know that there is a Norwegian band called Rammsund, and they sing Rammstein songs in the one of the Norwegian languages that's based upon Old Norse (Viking language) ^^

Sounds like a fun thing to do, and the language suits the music... (I know, I have that as my main language...)