I ran across that stackoverflow thread years ago I think, and if memory serves my favorite (though there are so many gems in there!) was something along the lines of
// I'm sorry, I'm so sorry.
Sometimes I'm also partial to something along the lines of
// What kind of idiot wrote this?
bad code goes here
// Oh, it was me.
I'm rather satisfied by the fact that the company I work for has a revision control submission tracker thing that keeps track of what people think are the funniest submit comments.