Do you have a few minutes to stack liquid? (And no, I'm not talking about a black & tan -- though it might be time for one of those too.)
In this short video, YouTube's "Brusspup" demonstrates how to combine household liquids of varying density in a glass, such that they stack up in a pleasant way. It's basically a way to make your own desk toy -- though I don't recommend turning it over, like he does at the end. Eventually that's gonna get messy, and then you're just pouring 30 ounces of oddly-colored crud into the trash. Anyway, if you've got ninety seconds to learn a simple trick, watch on:
From the YouTube description:
dark corn syrup
dish washing liquid
water (add food coloring)
rubbing alcohol (add food coloring)
Fill your bottle with water then pour it into a measuring cup, keeping track of how many total oz the bottle held. Then divide the number of liquids you want to stack, into the total amount of oz. That will tell you how many oz of each liquid you should pour into the bottle so that the layers are equal in size. Obviously if you want to have different sized layers, you can.
When you add the corn syrup and dish washing liquid be sure to let the liquid drop straight into the container so that it doesn't touch the sides. When you add the water, vegetable oil and alcohol, tilt the bottle and let the liquid run slowly down the sides. If you pour it in too fast, it will mix with the other liquids.
I don't recommended turning your bottle upside down, the colors may separate a little but it will never be as good as the original.