The Wilhelmus is the Dutch National Anthem,
a friend of mine (from the Netherlands) actually made a doom version of it.
(in 3 parts, because of the length of the song).

It's pretty cool, but very slow haha.
He does all instruments and vocals himself. I personally really enjoy his clean vocals

check it out here:

http://www.youtube.com/watch?v=o6SdDIMTILw (Part1)
http://www.youtube.com/watch?v=ThXlbgmfQ58 (Part2) > starts with clean vox
http://www.youtube.com/watch?v=3J4YPw1s_fY (Part3)