I grow many of the hottest peppers in the world. I'll list them at the end of this post.
----
From Wiki, and it is accurate as of now:
In 2007, Guinness World Records certified the Bhut Jolokia as the world's hottest chili pepper, 401.5 times hotter than Tabasco sauce.
On December 3, 2010, the Bhut Jolokia was replaced as the hottest known chili pepper by the Naga Viper pepper, which has an average peak Scoville rating more than 300,000 points higher than an average Bhut Jolokia - but still not higher than the hottest ever recorded Dorset Naga.
In February 2011, Guinness World Records awarded the title of "World's Hottest Chili" to the Infinity chili grown in Grantham, England. This chili rates at 1,067,286 units on the Scoville scale. Later the same month, on February 25, 2011, the title returned to the Naga Viper pepper with a rating of 1,382,118 Scoville Heat Units (SHU).
The current "world's hottest" is the Trinidad Scorpion Butch T, officially tested at 1,463,700 SHU.
----
The way these peppers are used in thier native countries is by either adding them to a substantial amount of stew, as with the "Trinidad 7-Pot" which will season "7 Pots of Stew", or by slicing the pepper open, removing the placenta and rubbing the butterflied pepper onto the outside of a roast prior to cooking it. This can be done by simply spot daubing or if tolerance to the capsaicin is high, by rubbing it on the entire roast.
----
From Wiki:
Capsaicin is the active component of chili peppers, which are plants belonging to the genus Capsicum. It is an irritant for mammals, including humans, and produces a sensation of burning in any tissue with which it comes into contact. Capsaicin and several related compounds are called capsaicinoids and are produced as a secondary metabolite by chili peppers, probably as deterrents against certain herbivores and fungi. Pure capsaicin is a hydrophobic, colorless, odorless, crystalline to waxy compound.
----
Birds are unaffected by capsaicin.
The same nerve endings in mammals that react to the surface pain of sunburn or scraping are the ones that also react in the mucous membranes to create the sensation of heat.
These peppers are NOT meant to be eaten "as is" or cooked into small quantities of food. They are simply too spicy.
Capsaicin is also used after extraction, in pepper spray in military and civilian police forces. It's also used in India by rubbing it on fence rails to dissuade elephants from entering fields and villages. The Indian government has also included it into small smoke grenades to deter elephants.
I grow and use:
1. Red Savina (800,000 on Scoville Scale)
2. Trinidad Scorpion (1.1 million)
3. Trinidad 7-Pot (1.1 million)
4. South African Fatalli (1 million)
5. Bhut Jolokia (1.1 million)
6. Naga Dorset (1.3 million)
7. St. Augustine Florida Datil (300,000)
These peppers are NOT used for flavor in anything. They are used as a way to spice up a dish without altering the intended flavor of the recipe.
The hottest peppers are used by the commercial food industry for spicing up many BBQ flavored items commonly found in stores. This only makes sense if you think about it.
Many thousands of tons of dehydrated pepper powder are used annually in the world for inclusion into prepared foods. These tons of powder have to be dehydrated, packaged and shipped all over the world. It only makes sense to use the hottest that are available and thus reduce shipping and handling costs.
The next time you eat some spicy food that lists a generic "Hot Peppers" on the label, you've probably just eaten one of the hottest peppers in the world, but in a quantity that makes sense.
If you want to end the hotness of a pepper, use a milk product. There are many "old wives tales" about how to stop the heat of a hot pepper, but scientifically, a chemical in milk products actually gets between the nerve ending and the capsaicin and allows the capsaicin to move along into the digestive tract. The best way is to drink some whole milk or cream and "swish" it around your mouth before either spitting it out or swallowing it.
If you use a strong alcoholic drink to do this, it won't do anything to stop the heat, but it will make you stop caring about it.