Trifoliate Orange are often hardy to zone 5.
They take brutal winters and polar vortex and laugh them off. Check out the hardy citrus threads for more details.
Trifoliate Orange or Poncitrus trifolia contain poncrin and other strong flavonoids that give the fruit a strong bitter taste of pine.
If you like the flavors of citrus and pine you might like trifoliate orange. I do.
Also you can just pick the fruit and leave it on the table to make a room smell nice. Its required to extract any juice anyway so thats a nice benifit.