I recently turned a lower-alcohol, lower-IBU weissbier into a vinegar...I took a few cups of beer, degassed it, added some unpasteurized vinegar as a starter, and let it sit at coolish room temperature for a few months. It developed a
gorgeous vinegar mother. The flavor on the final version is fantastic -- it tastes just like the stuff you'd put on fish and chips. I used it to spritz a pork shoulder on an extended smoke, and the end result was amazing.
Anyone else made beer or malt vinegar?