We have vinegar.

Well it's finally done.  Today I strained my pineapple vinegar into a clean mason jar and gave it a taste.  It tastes...well, like vinegar.  It is milder than apple cider vinegar, but perhaps slightly stronger than rice vinegar.  It has a flavor that is similar to the previously mentioned tepache, but much tarter and much less beery.  I'll have to post a follow-up after I've had a chance to try it in a few recipes.