The album features mashups of, among others, Eminem, P Diddy, Rihanna, Jay-Z, Placebo, Say Hi To Your Mom, Kanye West, Lil Wayne … You know, it may be easier just to list those artists not appearing.
It's free, but offered as a "pay what you want" pricing policy, with all proceeds going to 821 Valencia (a writing center dedicated to helping children). If you're looking to get good tunes and help out the young'uns, surf on over to the album's site and throw a few bucks his way.
*I don't know what the definition of "indie rock" is thought to be, but I didn't think the Red Hot Chili Peppers, Madonna, Something Corporate or LCD Soundsystem really qualified. Then again, Justin Bieber is considered to be an "artist," so maybe words just don't mean anything anymore.