Homemade Vinegar "Mother"

From Sally:

I checked this item out and it's a good piece of information which can be used. If someone finds a vinegar mother, it's a good thing to have for throwing in those left-over wines - any alcohol will turn to vinegar as will apple cider after it's become alcoholic - another way to create a mother.

http://www.thekitchn.com/thekitchn/good-questions/good-question-what-is-this-thing-in-my-vinegar-082249