Rock nostalgia is fueling pop culture at the moment, from musicals like "Hair" and "Rock of Ages" to video games like Guitar Hero and Rock Band. In the second of a three-part series on music and nostalgia, we look at rock revivalism. Our guests include Diane Paulus, director of "Hair;" Elizabeth Wollman, author of "The Theater Will Rock: A History of the Rock Musical from Hair to Hedwig;" and Elysa Gardner, music and theater reporter for USA Today.

Soundcheck blog: John Schaefer on nostalgia