Preheat oven to 300 degrees F. Line a baking sheet with foil; butter the foil and set aside. In a large bowl combine nuts and pretzels; set aside.
In a medium skillet combine brown sugar, water, and nutmeg. Cook and stir over medium heat until sugar is dissolved. Heat to boiling. Reduce heat to medium and simmer about 5 minutes or until mixture is thickened and syrupy. Drizzle sugar mixture over nut mixture, tossing to coat. Spread onto prepared baking sheet. Bake 10 minutes. Stir; spread on another piece of foil. Allow nut mixture to cool.
Break nut mixture into small clusters. Stir in cookies and/or sandwich crackers. Store in an airtight container up to 4 days. Makes about 16 (1/2-cup) servings.