Alice's Restaurant by folk musician Arlo Guthrie is not only a song, it's also a movie (Can you imagine putting enough storyline for a great full-length movie into 18,5 minutes?).
So its a movie roughly about the same thing as the song: To be not moral enough to go to Vietnam 'cause of littering.
It's a great movie, with a great soundtrack by Arlo Guthrie.
And, as mentioned before, it's the reason why Nixon had to leave the white house, cause he wanted no one to know him listening to anti-american hippie singer Arlo Guthrie. The full story told by Arlo himself is downloadable from www.arlo.net, on the thanksgiving live recording.