Lactobacillus is omnipresent in our bodies, from our stomach to our boogers, and is the main lactic acid bacteria used in sourdough bread and quickly brewed sour beers.

Most bacteria in boogers and sweat is pretty harmless stuff, and a lot of it can be used to metabolize some tasty compounds. Even some clostridiums (same category of bacteria as the disease c. difficile and an omnipresent type of bacteria in our stomachs) are used to produce esters in rum.