I really shouldn't have opened this link at work.
http://youtu.be/8qSkaAwKMD4 (The Viking Song. Literally.)
Not because it's NSFW; but because I lost the next several minutes to playing it through multiple times, trying not to laugh out loud (fortunately I had the earbuds on!), and then chasing down others in the series.
Such as:
http://youtu.be/3g61xASD-24 (William Wallace)
...gives new meaning to "playin' yer axe"...