United Airlines, North America premium cabin sale, London - Washington, D.C. First Class £2,595*, * include taxes, fees and surcharges

http://www.unitedairlines.co.uk/local/english/PB/fares/na_premium_cabin_sale.html

Qatar Airways, Business Class Offers, Bangkok Special Offers: ex: BKK to LHR/CDG US~$ 1,900

http://www.qatarairways.com/global/en/special-offers/thailand.html