A laundry hamper is one of the lightest items in the whole house to move, as long as you deal with what is inside it first rather than moving it fully loaded.
Pro tip: Use an empty hamper as a free moving box for pillows, stuffed animals, or extra blankets instead of buying another box.
Watch out: Do not move a hamper full of dirty laundry sealed up for a long drive; the trapped odor and moisture can transfer to nearby boxes and is unpleasant to open later.