It depends on the length of cruise and category of room. Many will tell you that it's not the best use of DVC points. If you want to post more details, I could look it up for you.
ETA - Your expected travel dates and number of people going would help too. Just an example: A 3-night cruise to the Bahamas could go from 67 points per person for the first 2 people to 248 points per person for the first 2 people.
Depends on length of cruise, itinerary if you want a 7 day cruise, cabin catagory, departure date and number / ages of those cruising.
If you have something specific in mind for this year, someone could look the points up for you - the 2005 point chart is on the Members' website. (I assume you are not a member). The 2006 chart isn't out yet.
FWIW, most who post here do not think using points to cruise is an economical use of DVC points. You can almost always do better by renting your points and using the proceeds to pay for the cruise. There are also some other restrictions/fees for using points that make booking for cash more attractive than using points.
dcibrando - The least expensive cruise (3 Day to Bahamas on the Wonder) for the least expensive cabin (cat 11) cruising in value season costs 67 points per person, based on double occupancy. Just an example.