Some websites will occasionally use popup overlays to display information on top of the current page. Typically these have an "x" button which allows them to be closed, but sometimes they don't, and you're forced to wait until the site lets you continue.
Overlay Blocker is a simple Chrome extension which enables you to close any overlay in a flash, whether it has an "x" button or not.
The add-on makes only one visible change to Chrome: right-click any page and you'll see a new "Remove overlay" menu option. If you're presented with an overlay, right-click it, select "Remove..." and it should immediately disappear.
That's essentially it. Overlay Blocker doesn't remember your actions, so it won't block the same overlay in future. It's just about removing overlays on demand.
It really couldn't be any more basic, but in our tests Overlay Blocker did a great job of removing irritating popup overlays on demand