All you need for this prank is:
(1.) A fork
(2.) One of those little creamer cup thingys
(3.) A victim
Step 1: Preparation
Step 2: The Prank
When the other person isn't looking, palm the creamer in your hand. Scratch your eye with your other hand, and complain about it itching. Do this for a short time, scratching and rubbing it, and then cover your eye with the hand holding the creamer. Make sure that the lid is facing outwards, so that it can be punctured. Pick up the fork with your other hand and poke the fork between your fingers so that it punctures the creamer. Scream and yell, and observe the reaction. Exploding eyeball...don't expect a second date.