Last year I started adding a category of "trip preparation costs" to our vacation fund. This allocated amount is used for new clothing purchases prior to the trip (especially helpful when traveling to a different climate than where you live). My Nana took her two kids on a trip to Maine last Christmas, they live in Louisiana! She had to shell out hundreds of dollars for parkas, boots, gloves, hats and other warm weather clothing they normally have no need for.
I like to get a trim/glossing treatment, pedicure and manicure before I leave for vacation. Not necessary of course but something I do buget for.
If you work an hourly/non-salary job without vacation pay in your benefits package dont forget to adjust your household budget as you will have an entire week of lost pay.
Also.... keeping with the pet sitter thread: have you provided the care giver of your pet with the means to pay for emergency vet care? I always leave my Mom (our petsitter) a blank check (signed) to use for the vet. I call our vet and let them know we will be out of town, let them know my Mom will be using a authorized check and she has full range to do what she seems appropriate in the event an emergency does occur. Luckily this has never happend but a good idea to plan for. I budget 250.00 for this. Upon returning home the 250.00 is put back into our annual pet care fund.
These additional suggestions are not just Disney related, just travel related. Others have listed great suggestions also.