Thought Christopher Lee releasing a metal album was unlikely? Here's a frontman who gives new meaning to the term 'cock rock' [You're fired - Bad Pun Ed].
Also in the metal mash-up category, here's Spongebob Squarepants doing his best 'death grunt':
And here's Sesame Street's Bert and Ernie going brutal:
Speaking of which, Cookie Monster has been known to indulge his heavy side:
As have various other Muppets: