The insular, elitist world of jazz is being rocked in more than one sense of the word. Young musicians, and even some old ones, are thumbing their noses at jazz purists and exploring popular forms of music, from grunge to indie-rock to rap. Flip through your local record store’s jazz bins and you’ll find pianist Jason Moran covering the rap classic ‘Planet Rock’ and the veteran organ player Dr. Lonnie Smith tackling an entire album of Beck songs. Some jazz artists are even borrowing a page from hip-hop, packing their discs with guest appearances by rappers.”