Run of dates to culminate in Crossroads Guitar Festival
New documentary explores musical couples' Seventies performances
German producer reinterprets Portland alt-poppers' club cut
Rockers relent and make music available through digital store
'Gangnam Style' turns into mash-up with '2 Legit 2 Quit'
Live clip comes from DVD celebrating band's 50th-anniversary tour
Hear the demo of the leftist alt-rockers' track
See Justin Bieber, Ke$ha and more stars make their entrances
Track was written for new Judd Apatow film
Band serves fourth term as musical guests
'See a Little Light' was recorded by filmmaker Justin Mitchell
Indie supergroup hit 'Late Show' with song from debut album
'Zeppelin's got such an epic quality to it that I think matches the tone of the show'
20-year-old had purchased two assault rifles, 400 rounds of ammunition