The toothpick star is an interesting experiment in which a person aligns 5 toothpicks broken in half into the shape of a star. The toothpicks must be closely put together like the image shown however and the halves must be connected by a small piece of toothpick.
To make the toothpicks into the shape of a star, you must drop a droplet of water onto the center. Once this is done, the water will move into the toothpicks at the same velocity. This will cause the toothpicks to spread apart and mimic the shape a star as seen below.
This occurs because capillary action causes water to be absorbed into the toothpicks. The water moves into section that was broken in half and continues to move outward all the way to the pointed tip. The capillary action inside of the toothpick causes the toothpicks to glide as they straighten.