Repurposing: Plastic Milk Cartons. Cut milk cartons so one fits into another. Use for anything you need quick sort and organize and stack. These are 1/2 gallon containers, one cut to 3 1/2 " tall and the other one to 4 1/2 " tall. To get straighten cut lines, put the carton into a drawer the height you want to mark the carton and use the drawer edge to hold the pen as you turn the carton.