I haven't seen precisely the interface you're looking for, but a few sites get close--lastminute.com has an "All Destinations" option. Choose your dates and it'll offer you a list of places you can go, sortable by price. They specialize in combination flight/hotel deals and last minute travel (surprise), but I've found their prices quite agreeable more than once. You can often get a hotel and a flight for about the same price as just the flight.

Similarly, Yahoo, Kayak, and many other travel sites have "Deals" buttons that will offer you a range of destinations and quotes. If you find a destination you like, you can then see the fares to that destination arranged on a calendar.