I hope this isn't too cliche... I cry every time I hear eruption. I don't know why it is so powerful to me. The amount of work and passion put into it blows me away... Also Thistle and Weeds by Mumford and Sons is the most recent song to change my life.
The song which has impacted me the most I would have to say is off of Ray Charles's country album... His cover of The Ring of Fire.
http://www.youtube.com/watch?v=46fy-DRToGM
its not totally rock, but it is rockin!