Volatile anesthetics are the main drugs we use for general anesthesia. Currently the most popular volatile anesthetic is sevoflurane. The most interesting thing is that we have no clear idea about how volatile anesthetics work. Our main anesthesia textbook: “Miller's Anesthesia” 10th edition has a 29 page chapter about the mechanisms of action for inhaled anesthetics and they focus on receptors/ionic channels as the most likely site of action. However, volatile anesthetics work on all life forms with a huge variety of receptors/ionic channels. Surprisingly, general anesthesia seems to be a natural phenomenon. Some of the original volatile anesthetics (e.g. chloroform and nitrous oxide) are produced by bacteria and fungi. Why would nature produce volatile anesthetics? Maybe different life forms anesthetize each other or themselves. The article “Understanding of anesthesia – Why consciousness is essential for life and not based on genes” by František Baluška et al, Commun Integr Biol. 2016 is a good overall perspective. A fun fact is that ethylene was used as a volatile anesthetic in humans in the 1920s: good overview here. Nowadays, ethylene is used to ripen fruits in stores. The problem with ethylene as a volatile anesthetic is that you need a lot of it, something like 85%, for general anesthesia.
One experiment that any anesthesiologist can do is to anesthetize the touch sensitive plant: Mimosa Pudica. It is very easy to grow the touch sensitive plant and its response to touch is very obvious. You can use sevoflurane to anesthetize it. The touch sensitive plant loses its response to touch under anesthesia. One article describing anesthesia in this plant is here.