Parents who tell their kids not to play with their food are sorely misguided; there is no better way to enjoy eating than to play with food. Mashed potatoes are wonderful when you can ski down the hill, land in a gravy lake and then destroy the landscape with a single scoop. Many babies (rightfully) refuse to eat jarred food unless the dripping spoon is lifted "up the hill, down the hill, around the hill and into the tunnel."
A banana tastes much better if it is a pig.
Step 1: Tools
All you need is a banana and a knife
Step 2: Make the Head
Cut the snout by making a small slit on the bottom of the banana.
Make eyes by poking the skin with the tip of the knife above the snout. You won't see them much at first but they will soon turn black.
Cut the ears by making two small flaps on both sides, above the snout and eyes.
Cut the neck by cutting about 3/4 way through the banana, behind the ears.
Step 3: Make the Body
Cut the stem on the "underbelly" side, so it is still attached to the pig's back, then peel off the back till it just reaches the pig's neck. There should be a small piece of banana peel left intact between the neck and the peeled back.
Step 4: Play... Then Eat!
When you tug on the stem and peeled back, the pig's head goes up and down. Watch this 48 second video to see it in action. Sticking a bead in the pig's mouth is optional, however loud oinking sounds and snorts are absolutely mandatory to get the full effect.
PS: Since I am entering this instructable into the laser contest, let me tell you what I would do with a banana and a laser cutter.... I'd slice up the banana and laser cut the pieces into letters, to make the cereal equivalent of alphabet soup. I bet it would be delicious too, with the burnt, sizzling edges...