I've come across several organizations that offer free vacations to troops returning home from deployment. Each of these organizations is usually the effort of a small number of individuals or merchants, each donating time in their own vacation home, or a gift certificate for vacation and travel related services.
This is a great way to help troops and their families one at a time. If you have a vacation home, offer up a free week to a troop. They are very responsible, and are used to moving in and out smoothly. As an individual family, you could contact a military base or hospital near your home. Check in your area, there may already be a cooperative that is organizing vacation donation to troops.
If you have the organizational skills, draw together other families or hotels/Inns that would offer free vacations to troops. Try to get local merchants and restaurants involved for vacation activities. If you have a time share and wont be using it, offer it up at a local base. You could get help on the base from the MWR (Morale Welfare Recreation) office or the Family Support Office.
Deployment actually costs a lot of money. There are lost wages, the need for child care, phone bills, the little travel items that aren't covered, and repairs and maintenance that have to be hired out when the troop (or troops in some double military member families!) so there isn't often money left over for vacation. It would mean a lot to a military family to have a spot to celebrate their reunion.