Hainan Airlines currently has some good fares for the direct flight on their new 787 Dreamliner from Boston to Beijing. It’s just $545 for the Round Trip.
The departure dates are all in September (ITA Matrix shows the fares) so you need to be very flexible.
The fare books into Q and actually earns 50% with Alaska Airlines Mileage Plan (or AirBerlin’s TopBonus). It is 13,434 miles in the air.