Among the famous hippies have been many artists, musicians, writers, activists, and spiritual leaders who have embodied the spirit and values of the movement. Some examples are: John Lennon: Lead singer and songwriter of the Beatles, who wrote songs such as "Imagine" and "Give Peace a Chance", which have become anthems of peace and love. Bob Dylan: Singer-songwriter and Nobel Prize in Literature, who influenced folk and rock music with his poetic and engaging songs, such as "Blowin' in the Wind" and "The Times They Are a-Changin'". Jimi Hendrix: Psychedelic rock guitarist and singer, who revolutionized electric guitar technique and sound with his virtuoso and innovative performances, such as "Purple Haze" and "Star Spangled Banner". Janis Joplin: blues and rock singer, who expressed her emotions and life experiences in her powerful and scratchy voice, as in "Piece of My Heart" and "Me and Bobby McGee". Timothy Leary: psychologist and writer, who promoted the use of LSD as a means to explore the mind and reach higher levels of consciousness, with his slogan "Turn on, tune in, drop out".