Shepard performed Spalding Gray's final monologue, "Life Interrupted", for the audiobook version, released in 2006. In 2007, Shepard contributed banjo to Patti Smith's cover of Nirvana's song "Smells Like Teen Spirit" on her album "Twelve". Although many artists had an influence on Shepard's work, one of the most significant was Joseph Chaikin, a veteran of The Living Theatre and founder of The Open Theater. The two worked together on various projects, and Shepard has stated that Chaikin was a valuable mentor.