Procedure
Take a drinking glass filled with water and a clean fork. Dunk the end of the fork into the water. You can control whether the water drips off when you pull it out slowly, by the angle, or by how fast you pull it out. It takes some practice, but when you pull it out slowly and straight up, the fork comes out dry and will not drip water.
If you pull it out fast and at an angle, it will drip lots of water. With practice, you can amaze your friends by altering your lifting techniques just at the water surface.
Scientific Principle at Work
Hydrodynamic flow is governed by rheological (the science of flow) properties. This is just a fancy way of saying that liquids move a certain way according to the laws of gravity and physics. The viscosity and thickness of the water-film control how fast it flows off the ends of the fork.
Note: If you're under the age of 18, be sure your parent or guardian knows what you are doing. Some of these experiments require the use of simple household tools, such as scissors and knives, and some could make a mess. Ask your parent or another adult to help.