Let me think...
An Even Steven Psychonauts Holiday Story: Raz tries to explain the purpose of Chanukah to Lili, while Lili tries to explain the purpose of Christmas to Raz (Raz: "I've long wondered what the Coach meant when he said, 'Jesus H. Christ!'")
From Russia With Love: Mikhail's struggles to get his Christmas present to Maloof mailed to America on time
To Russia With Love: Same situation as above, with Maloof and Mikhail switching roles...actually, these could both be combined into one story
Bobby Saves Christmas: A heartwarming tale about Bobby doing a good deed for the holidays...heavy on the sentimental sap
A Dogen Boole Christmas: Dogen struggles to find the true meaning of Christmas amidst all the holiday commercialism ("Of all the Dogen Booles in the world, you're the Dogen Booliest!")
It's A Blunderful Life: Crystal has decided to kill herself for real - and gets a visit from her guardian angel, who shows her what the world would be like if she had never been born, yada yada yada (Clem becomes a lonely, friendless Goth, and Raz is never able to become a Psychonaut, because Crystal wasn't there to cheer him on)
I'll try and think of more.
"In the end, Razputin, aren't we all just dogs playing poker?"