I'm glad I've been able to answer a mystery for you cecil39! The cultivation of a vinegar mother was one of the first practical experiments I did in microbiology classes at uni many years ago. I'm afraid it's left me with a dislike for the organism as I've been chucking out half-used bottles of malt vinegar at home for years once they become cloudy, which can be indicative of the organism having colonised the vinegar although there are sometimes other reasons.
Having said that, we continue to fascinate students to this day with a vinegar mother culture and I'm constantly surprised about the number of people who have never heard of it. It's necessary to use unpasteurised vinegar for the job, which is becoming increasingly difficult to obtain nowadays.