Taken from Martin Lewis's - moneysavingexpert.com
UPDATE - USE THIS LINK: http://content.announcements.uk.com/TTLEMAIL/EastCoast9pounds_02_landingpage.html?WT.mc_id=EMAIL000000135
£9 London to York/Edinb & more starts Friday
From Friday 1 May ticket booking site The Trainline is offering 350,000 off-peak, single fares at £9 anywhere along the National Express East Coast train line. This includes London, Peterborough, Doncaster, Leeds, York, Newcastle, Edinburgh, Glasgow & Inverness.
You can book between Fri 1 May and midnight Tues 5 May for travel between Monday 1 June and Sunday 26 July 2009. To book the ticket simply visit the The Trainline* from Friday.
The further you're travelling, the bigger the savings. For example at the time of writing the cheapest ticket to Aberdeen from London was £54 one way so find a £9 fare and that's saving of £45.
Be aware though, you can't use any other discounts or railcards with this offer, so do compare the cheapest ticket available with your railcard to the £9 offer. When you book the ticket online you'll get a voucher which you must print out and travel with. Availability between Thurs 2 July and Sunday 5 July on trains is limited and the offer isn't available on shorter, less busy routes.