I have a detailed budget that includes:
- Gifts for everyone I need to give to, from DD14 (incl stocking) to my mother/siblings/nephews to the gardener and everyone inbetween.
- Travel costs to my Mother's: plane tickets, rental car, rental car gas, cat boarding, airport parking, checked bag fees
- Christmas cards
- Wrapping paper/bags/etc (usually a very low budget because I pick things up at after Christmas sales)
- Shipping of gifts
- Christmas Tree and other decorations (we get a new nutcracker every year, I grab a bunch of poinsettias at Home Depot on Black Friday for $1 each)
- Christmas outfits for me/DD14. It's just not Christmas without a new outfit to wear for the day

I like to pick them up during the summer sales though - I got great sweater dresses for both DD and I this year for 80% off.
- Activities like going to see the Nutcracker ballet, buying a new Christmas movie for our weekly movie night, etc.
- Hostess gifts: my brother hosts a family get together Christmas Eve and it's tradition for me to bring a box of Sees chocolates. Other events throughout the season usually require one or two other hostess gifts.
- Extra grocery shopping: While at my mother's I usually do a couple of major grocery shopping trips to get things for meals and such. Tradition is that I cook tortilla soup one night for the whole extended family, other nights I cook things just for me, DD14, my mother and maybe a random brother or two.
So basically my Christmas budget includes anything over and above my standard monthly budget.
I won't mention the total. Travel costs especially make it a bit obscene. I'd love to cut it, but I have it down as low as I can get it without sacrificing things I feel are worth it.