For the leisure travellers, with tight budgets....
one good choice from JFK or BOS to LHR is Icelandair.
Afternoon (7 pm ) daily departures from USA, connection to Reykjavik-Keflavik (KEF) for 2 hours early in the morning, and arrival at LHR at 11.30 am. (when i was travelling we arrived earlier). Not bad schedules..
Iceland uses B 757-200 which is nice but a bit cramped, the food is good-drinks are served, the FA's friendly (and some of them very attractive as well)
and above all the prices are unbeatable
I won't mention the price for matters of deontology but I tell you that I got a really cheap return ticket (in the range of the seating capacity of an A-300 B4)
Does anybody knows any better deals, on a regular basis, except some special ones?