Hayseed Dixie-New bluegrass band with bluegrass covers of rock classics such as the Pistols Holidays in the sun and Motorheads Ace of Spades
http://youtube.com/watch?v=jpNfPP3FKRA
http://youtube.com/watch?v=cYJUywl7CFw
Los Lobos- Old band, you may recognise them from:
http://youtube.com/watch?v=YicJPLT1dWU