The music that plays in Paper Mario's intro is based on the classic children's song "Inchworm".
Paper Mario Intro (resemblance becomes really obvious at 0:42):
http://www.youtube.com/watch?feature=pla...1DnY#t=14s
Inchworm (Sesame Street version at 0:26):
http://www.youtube.com/watch?feature=pla...cjfY#t=26s
Let me say first that this is not a note-for-note carbon copy of the same song. Obviously Yuka Tsujiyoko played with the melody a bit. But seeing as how Paper Mario begins with a children's book, it's a safe bet that a famous children's song like Inchworm was the inspiration for it's opening music.
EDIT: Youtube Doubler for extra proof:
http://youtubedoubler.com/?video1=http%3...meahwahwah
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