@AnswerMan: What you are talking about is called a twin tub washing machine. The advantage is the manufacturing cost is low, as is the product cost. However, they take up a lot of extra space compared to a washing machine with the same capacity.
Also, it's important to note that mini washing machines don't have a spin cycle, only portable washing machines costing $200+ do. Mini countertop spin dryers are available at The Laundry Alternative.