While trying to come up with a name for my homebrewing operation (everybody has to have a name for their brewery even if it is only a couple of buckets and carboys in your basement, right?), I remembered reading a section in a book called North German and Netherlandish Popular Tradition and Superstitions.  There was a section called The Subterreneans Lick Up The Milk that says:

"About seventy years ago little underground beings were seen in many farms in the Wilstermarsch, who did little more than accompany the maids and men home in the morning after they had been milking, and sedulously lick up the drops of milk that had been spilt. But when in measuring out nothing was spilt, they would overturn all the vessels and run away. These people were about a foot and a half high, wore black clothes and a peaked, red cap. Wherever they came, people thought they brought a special blessing on the house. In the Frisic islands the housewives have frequently observed, when brewing, that the little people usually came in the shape of toads, and licked from off the floor the new beer that had been spilt. No one does them any harm, and the beer so spilt must be left for them, as well as the crumbs of bread that fall from the table."