The teaser video of the Durian Open Movie project used quite an epic accompanying music by Denny Schneidemesser. A lil’ searching should bring you either to his website or his newgrounds account which hosts his other music scores.
And the best part is, majority (or all?) of his music is licensed a CC-BY-NC-SA license which means it is perfectly legal to use his music scores in your personal, non-profit YouTube videos as long as you give him credit. You can also alter the work as long as it should come with the same CC-derivative license. :3
Right now, I’m listening to the said epic music titled “Entering the Stronghold” over at his NG page.