Gmail's Mysterious Grey Box

There’s a small grey box rendered in an iFrame in the top left hand corner of Gmail, and TechCrunchIT is trying to figure out what it is. The icon is a ten by ten pixel graphic with a diagonal line across it, with one half in black and the other in gray. It isn’t an inline image, as you can not highlite it or select it in your browser, nor right-click on it. There is also no reference to the image within the style sheet for Gmail.

So what is it? Since it’s being rendered in an iFrame it’s difficult to say. We’ve been emailing back and forth with Google since Wednesday but so far they haven’t said what it is. What’s your best conspiracy theory? The most elaborate/entertaining or most accurate comment (on TechCrunchIT) gets a free TechCrunch Tshirt.