Jade Empire (2005 Bioware) - I don't remember a whole lot about this game except that it was awesome. Same developers that brought you Dragon Age, Mass Effect and Star Wars: The Old Republic. Shockingly, I don't own this soundtrack. But I'm about to.
And who can deny that cover art? Check out the guy!
Special Mentions: Jaws, Joust, Journey
Jimi Hendrix - Of course it's Jimi Hendrix for J day. I'm a lefty guitarist. Here's a tune for ya!
Journey - They're a close second on my list. Here's another tune! Wait. That's probably not the one you're thinking of... Try this.
Special Mentions: Jane's addiction, Judas Priest, Joan Jett