Instructions:Special Fare for Arsenal fans. Works for anyone though, as long as flight originates in UK. Gave me £12 off a booking of £700.
To view this deal on the Emirates website, try searching for a flight originating outside UK with the promo code UKARSN1 typed in... you will be redirected to the page showing the offer.
UKBARC1 still works for Barclays card holders, but gave me only £9 off the same booking.