William Carlos Williams wrote one of my favorite poems ever. . . 

" This is Just To Say"

I have eaten the plums
that were in the icebox

and which you were 
probably saving for breakfast

forgive me they were delicious
so sweet and so cold

This not quite an apology apology poem has sparked many people to create their own in a similar style. . . my favorite WCW inspired poem happens to be written by Andrew Vecchione, a sixth grader.  

"Sorry But it Was Beautiful"

This is just to say
sorry i took your money 
and burned it
But it looked 
like the world falling apart 
when it crackled and burned.

So i think it was worth it.
 After all
you can't see the world fall apart every day.