Simply add it to your cart and during the checkout an extra $100 will be taken off the list price, bringing it back to the lowest price it's ever been once more.
At this very moment, you can pick it up for $849 at Amazon. A nice saving, sure, but it's about to get better for those in the States. It's had a standard $50 / £100 knocked off the $999 / £999 price over recent weeks. Right, let's start with that MacBook Air model.