Professor Meadows, an immunologist at Washington State University says, "The drainage from your nose is largely made up of mucous and fluid." The internal portion of your nose is lined with something called a mucous membrane, same as the inside of your stomach. In the stomach, mucous defends you against yourself. Its slimy, lubricating coating guards the lining of your stomach against the hydrochloric acid that helps digest your food. In the nose, mucous has two roles. Along with tiny hair-like projections called cilia, it traps dust, bacteria, and other small particles breathed in with air. Working together as a filtering team, they make the air easier to breathe, cleaner and more free of such harmful things as bacteria. Basically, snot is a mixture of water and the particles that it and the cilia filter out. It also includes shed epithelial cells, dead leukocytes, dead bacteria and their products, mucin, and inorganic salts. Epithelial cells line all the inside surfaces of your body, including your nose. They die and are shed much like the skin that peels off in the shower when you have a sunburn. Mucous acts like a shower in your nose, washing away the elderly cells. White blood cells, or leukocytes, are soldiers in the war on bacteria and other foreign material in your nose. Leukocytes protect your nose (and your body) by swallowing all that bad stuff. Then they die and are washed out in mucous. Mucin is a sugar made by the mucous membrane that lines your nose. It is one of the products that helps moisten, lubricate, and protect the inside of the nasal passage. The inorganic salts are materials breathed in that can harden and become…boogers.. Reference Link: http://www.wsu.edu/DrUniverse/snot.html

Mucus?

Mucus, which is made by some membranes in your nose, and is basically just some proteins and salts suspended in water. It's supposed to help catch germs and things that go up your nose so they don't make you sick. (To combine two above answers and put it into SIMPLE English.)

Sugar and spice and everything nice!

It is a viscous colloid containing antiseptic enzymes (such as lysozyme) and immunoglobulins. Mucus is produced by goblet cells in the mucous membranes. Why you find it tasty is beyond me I'm afraid.........

Apparently you're not the only one.

I think its made of a mixture of mucus and particles from the air that become stuck in it- including germs, pollens, particles from air pollution (including other peoples' farts and bad breath) and whatever else may be in the air where you spend your time. I don't know why you think its tasty but I liked the salty taste when I was a little kid and I liked it when it got dry and crunchy sort of.You could try tasting your earwax also.

what does it taste like ?