Check out this writeup on 13 Rule-Breaking Films.
How can you NOT be inspired to write a rule-breaking song after reading that?
I guess it's not as big of a deal to write a rule-breaking song, since a song can be written and recorded in mere hours for no money, whereas a movie involves hundreds of people and millions of dollars.
But that being said... what are your favorite rule-breaking songs?
Feel free to include a link to your own rule-breaking song, here, in comments. :-)