Not a very good workout

My left knee started aching after a few exercises, in a way that made my crunches and back arches problematic. So, a short workout. And then my feet got wet from slogging through the slush on the way home.

( Nonetheless, by the numbers )

Looking at the numbers, call it a bit over half a workout; and, writing that, I realize again that while I do the cardio, and know it's good in itself, not just as warmup, I'm not counting it as one of the things I do when I count how many different things I've done in a trip to the gym.

Information wanted: traveling to London on short notice

I may need to fly to London for a few days, on fairly short notice, quite soon. Obviously, short notice makes it more expensive, but we'd still rather not spend more than necessary.

Just to complicate things, I might be looking for an open-jaw Boston (BOS) to London and back to New York, rather than a straight NY-London round trip.

I think Heathrow or Stansted works at that end; at this end, it can be JFK or Newark (EWR).

If any of you either knows useful things yourself (like where to look online, especially for open-jaw tickets) or knows a travel agent who does this sort of thing, please let me know. I'd normally just book my own ticket for something like New York-London, but "normally" allows a good deal more time for planning.