Place the Brie in the slow cooker stoneware, if using 1-quart size. Otherwise, cut a 12-inch (30 cm) square of foil; center Brie on the foil, then fold the foil up around the Brie, scrunching it around the sides to form a foil dish, leaving the top exposed.
In a bowl, combine the cranberries, brown sugar, water, vinegar and pecans. Spoon this mixture on top of the Brie.
Cover and cook on High for 1 1/2 hours or on Low for 2 1/2 to 3 hours, until center is soft and the cheese starts to bulge around the edges. If you are using a mini slow cooker without a choice of heat settings, check the Brie after 1 hour.
Serve from slow cooker or transfer carefully to serving dish. Serve warm with crackers.