Thomas the Train snack train. It's just 3, two packs of aluminum loaf pans from Walmart at 2.50 each (with plastic lids-great for leftovers), a roll of black electrical tape (.60 cents) and of course, Thomas.
It's called a "Punch Box" and it's a great alternative to a pinata. (Four-year-olds with big sticks can be a little scary sometimes.) Instead of beating on a pinata with a stick, each child punches through one of the pretty colored circles in order to grab the prize inside.