This is the most amazing thing I've seen all day! Stop and watch this video right now. Brusspup, maker of astounding optical illusions, let water flow past a speaker set to a particular frequency:
Run the rubber hose down past the speaker so that the hose touches the speaker. Leave about 1 or 2 inches of the hose hanging past the bottom of the speaker. Secure the hose to the speaker with tape or whatever works best for you. The goal is to make sure the hose is touching the actual speaker so that when the speaker produces sound (vibrates) it will vibrate the hose.
Set up your camera and switch it to 24 fps. The higher the shutter speed the better the results. But also keep in the mind that the higher your shutter speed, the more light you need. Run an audio cable from your computer to the speaker. Set your tone generating software to 24hz and hit play.Turn on the water. Now look through the camera and watch the magic begin. If you want the water to look like it's moving backward set the frequency to 23hz. If you want to look like it's moving forward in slow motion set it to 25hz.
-via Colossal
I also wonder what it looks like in person. I wonder if you shot the 24 Hz at 30 fps if it would basically look "normal".
To address the above question, I wonder if it would look any different at 48 fps, because the tone is still 24 Hz (24 sound waves/second). Maybe it would look like half as many waves? I imagine 48Hz at 24 fps would have the same effect, but double the amount of waves.