If you are looking for amazing fares, though, the place to look is Dublin.
BA is currently offering fares from Dublin via London and onto North America for as little as Euro 1,200, or £945.
The Euro 1,200 fare is valid to most of the East Coast destinations plus Calgary and Las Vegas. Other destinations in North America will cost a little more – you need to play around on ba.com.
Here is a Boston screenshot showing it works, this one comes out at Euro 1,215:
The fare rules involve booking by November 12th and travelling between November 22nd and September 5th 2015 – a huge period.
A Saturday night stay is required. Tickets are non refundable. In theory the dates can be changed for Euro 300 but that would trigger a reprice on the day of the change which is unlikely to be attractive.