Paula's Popcorn Nut Balls

In an extra large mixing bowl, toss together nuts and popcorn. Set aside. In a medium saucepan over high heat, bring sugar, water, syrup, vinegar and salt to 260 ° (hard-ball stage) on a candy thermometer. Stir in vanilla. Pour hot mixture over popcorn and nuts, tossing gently to coat. When mixture is cool enough to handle, rub hands with room temperature butter and form popcorn into 4 inch balls. Place on waxed paper until cool. Wrap in clear plastic wrap and tie with a decorative ribbon. Note: Use caution when handling hot syrup. Syrup stays especially hot on nuts.