In the end, the fun that you have when lowering your voice after inhaling sulfur hexafluoride. Which happen when the gas weight slows the sound waves in your vocal tract. Just like Helium that works in the opposite way. However, Sulfur Hexafluoride is an uncommon chemical to breathe in. People even more familiar to helium.
This is because Sulfur Hexafluoride is more expensive and has more toxicity probability than helium. There are tricks to use this non-toxic chemical by inhaling oxygen before it. There are even breathing technique that you can do if you fill sign of discomfort. Basically, you need to use the Common Uses Oxygen Element to balance this substance when inhaling it.