Wrapping holiday gifts can be tough. But imagine how much harder it would be if your gift were a single drop of oil–you’d have to be as clever as you were cheap to figure it out. Now, scientists have discovered how to do just that. First, they coat a pool of water in a thin film of floating plastic sheets. Then, they drizzle in droplets one by one, which hit the plastic with enough force to drive them below the surface. That causes the plastic “wrappers” to envelop the drops—and seal them in a near-perfect seam. Such packaging could be used to encapsulate oil dispersants and release them steadily over time to fight oil spills. What’s more, the technique also works with multiple layers of thin materials. Down the road, capsules with an inner coat that helps preserve a cancer drug and an outer coat that delivers it to cancerous tissue could target drugs to tumor sites. So even a tiny drop might be a gift worth wrapping, after all.