In November of last year, guitarist Ryan "Mega Beardo" Postlethwait released a concept album, Belmont, based on the original Castlevania. Similar to the works of The Protomen or The Megas, it is a rock opera that tells the tale of Simon Belmont and the challenges he must face on his march towards Dracula's lair.
I only learned about Belmont last night when Ryan tweeted that he has made it free to download through tomorrow, June 15. If you miss the cutoff and still want to cop the album, I doubt you'll have to pay may more than a few bucks, considering the physical CD only costs $6.
Speaking of the physical CD, it comes bundled with a copy of his first game-themed album, Mega Beardo: A Mega Man 2 Guitar Tribute. Released in April 2010, it is a more traditional, instrumental cover of the entire MM2 soundtrack, available for whatever you wish to pay. MM2 music has certainly been done before, but it's always nice to check out a new interpretation, especially if it's technically free. What's to lose?