And that stuff (ethyl mercaptan, the world's smelliest substance according to the Guinness World Records) is the stuff that makes you smell the gas you use at home. Gas is odourless, and they have to use ethyl mercaptan so you can smell it if there's a gas leak -
Ethanethiol (common name ethyl mercaptan) is a colorless liquid that has a strong odor, resembling that of rotten eggs. The odor is familiar to many people who use natural gas and propane for cooking and heating, as it is used as an additive to give those normally odorless fuels a distinctive smell. The smell acts as an alert that there is a gas leak. The chemical formula for ethyl mercaptan is C2H5SH. It was discovered by Maxwell Burrows.
According to the 2000 edition of the Guinness Book Of World Records, ethanethiol is the "smelliest substance" in existence.
Ethanethiol is toxic and in large doses will cause headaches, nausea, and a lack of coordination, as well as liver and kidney damage. The doses of ethanethiol from natural gas are not toxic.
Butyl seleno mercaptan is the stuff that skunks spray to produce that awful smell.
Other awful smelling compounds are -
These man-made compounds are more complex and arguably stinkier than the simpler molecules. They also have catchy names.
Five ingredients are used to make this sulfur-based chemical, which smells of rotting carcasses. "Who-Me?" was developed during World War II so that French resistance fighters could humiliate German soldiers by making them stink. In practice, it was very difficult to restrict the application of the chemical to the intended target.
"US Government Standard Bathroom Malodor"
American chemists developed this combination of eight molecules, said to emit a stench resembling that of human feces, to test the effectiveness of air fresheners and deodorizers.