Liturgy, an American black metal band, have done a really off the wall cover of Shellac’s ‘Prayer To God’
Now you would be expecting an even darker, heavier take on the song but Liturgy have really upped the ante stripping the song down and recording an acapella version of it.
Stripped down to main man and manifesto-penning provocateur Hunter Hunt-Hendrix, Liturgy’s take on Shellac’s “Prayer To God” is àsung in a trancesdental way over an increasing pile of vocal loops in a really hypnotic take on the song.

In depth Shellac interview here.
Prayer to God has had a fair few covers done of it. This folk version by Solander is my favourite httpss://www.youtube.com/watch?v=1k3BLtRi-B4&feature=youtube_gdata_player