Interesting--a semi-Gregorian chant version of Metallica

Metallica's 'Nothing Else Matters' as covered by Gregorian on their album Masters of Chant:


They have a host of secular songs, many of which are on YouTube. Some examples: 'The Sound of Silence', 'Ordinary World', 'Losing My Religion', 'Blasphemous Rumours', and 'When a Man Loves a Woman'. The German band blends music with the chant, so it's not true Gregorian chant, but the harmonies are beautiful nonetheless.

Here's their version of 'The Sound of Silence', which is quite powerful:


For an example of true Gregorian chant, here is 'Dies Irae', from the 1994 album Ego sum Ressurectio:


My favourite version of 'Dies Irae', though, is the one by Mozart in his Requiem:


Okay, that's enough videos for one night!