I'm not too familiar with Ryan Adams but he does a really cool cover of Wasted Years.
http://consequenceofsound.net/2011/08/check-out-ryan-adams-covers-iron-maidens-wasted-years/
Here is a list of his top 13 metal songs, quite the assortment.
http://www.brooklynvegan.com/archives/2008/12/the_13_metal_so.html