I saw the UCO Ice Cream Ball (TM) in the LL Bean catalog and I was intrigued. Basically, you chuck in the ingredients in one side and the rock salt and ice in the other side then roll it about to make fresh ice cream.
The contraption is marketed to hikers and campers, but imagine rolling it back and forth with your toddler, or maybe your pet! After the experience we had with the Icee Maker, I don't know that I'd buy this before trying it... but it looks slick. It even comes with recipes!