I am wondering how to make an angled element that acts as an arrow, attached to a tooltip. I've seen this done by Google Accounts, and I have attached a screenshot. It appears they are achieving this with a couple of span elements.
I can't figure out from their HTML/CSS how they did it... My only idea is to use a CSS3 rotation on a regular div, or an image, but I'm guessing there's a more basic way.
Can anyone give me a hint? I'm not looking for a full solution, I'm just stumped about how to approach it. Also it's not about the tooltip itself, it's about that angled element.

EDIT: Here's a related question. They are using transparent borders, border-radius and box-shadows?
