Following Ozstamps alternate destination idea - though this is much further away - more complicated, yet more miles ...
I throw this out for your consideration.

I have twice gone to Beijing in December (pre-Xmas and post-Xmas) and both times (2001&2002) the H fares from IAD were $850-$912 (inc tax).

These flights were also taken in order to get a free stopover in NRT. (otherwise a scary $2000 fare from the East Coast in Dec.)

I'm no routing specialist but who knows, it may be possible to fly IAD-ORD-PEK stay overnight (gets in at 5) then fly PEK-NRT-BKK. (PEK-NRT in the am). On the way back fly BKK-NRT-SEA/IAD.

Would this be one Sweetspot? Ozstamps our resident "how far can you go on one piece of paper" expert may know.

Price reference: I'm flying IAD-BKK in early Dec $740 W fare; $950 H fare.