For ice cream fanatics, it may be hard to imagine anything more fantastic than a parlor filled with 47 flavors of your favorite frozen treat! But if you bypass the lollipops and licorice and beeline for the bathroom, you’re sure to find a surprisingly memorable sight — another of Sloan’s celebrated sensory experiences — its see-through bathrooms! When the restroom is empty the bathroom window visible to the parlor is clear, but once locked, a layer of fog blocks the view. Here’s the science behind it: sandwiched between the two panels of glass is a mixture of polymer and liquid crystals. A constant electrical current keeps the crystals in line and the glass transparent. But when the door handle is locked, the current is stopped, the crystals fall, and the glass looks clouded. Of course, you’ll still wonder when you take a seat whether or not it works! How’s that for sinfully sweet!