Some of the commemorations will be as appropriate as a 50th-anniversary edition of the Monterey International Pop Festival, on the same dates (June 16-18; www.montereyinternationalpopfestival.com) and on the same stage as the original that spotlighted Jefferson Airplane, Jimi Hendrix, The Mamas & The Papas, The Who, Big Brother and the Holding Company (with Janis Joplin), Otis Redding, the Grateful Dead, and many, many more. (Most of the original performers, due to fate, will be no-shows this time.) That festival drew thousands - an accurate count, again, is elusive - and pretty much set everything else in motion.