For Gen Xers (born 1965 - 1980), my vote goes to the brilliant 1977 punk song "Blank Generation" by Richard Hell and the Voidoids.
For Baby Boomers (born 1946 - 1964), like me, I'll go with The Beach Boys "Good Vibrations" released in 1966.
I imagine that 80%+ of Pinsiders were born between 1946 and 1980. I think that "Blank Generation" was more influential lyrically whereas "Good Vibrations" was more significant musically. Which songs do you think were impactful to your generation?