Winter time pies other than apple?

http://www.food52.com/recipes/10115_tangerine_and_almond_shortbread_tart

For me winter is time for cream pies, chocolate or banana or for a lemon meringue pie. If you see key limes, make a key lime pie.

Pumpkin pie http://www.101cookbooks.com/archives/spicekissed-pumpkin-pie-recipe.html
And use pureed butternut squash - much richer in taste than pumpkins,

Pears are wonderful! This recipe of mine was part of a contest with a pear theme, and there are many other excellent choices --
http://www.food52.com/recipes/14441_new_england_pear_harvest_tart
(I've moved to a pastry crust when I make it now. it's the custard that makes it so good, crust optional.)
Another contest was specifically for winter tarts --
http://www.food52.com/contests/224_your_best_late_winter_tart_sweet_or_savory
Good selection of citrus, nuts...

This Kumquat Shaker Pie is perfectly seasonal: http://www.food52.com/recipes/15779_kumquat_shaker_pie