Marco Materazzi has finally revealed what he said to Zinedine Zidane to earn that headbutt. Seems it went something like this:

Materazzi had been pulling Zidane's jersey, causing ZZ to remark: "If you want, I'll give you the jersey later." Materazzi's not so subtle reply was "I'd prefer your sister."

And that's it. Amazing how important this all seemed two months ago, and how trivial it is now.