http://www.ilovepickles.org/articles/usesforthejuices.html
I save my jalapeno juice and add it to my pickles and olives. And I save my olive brine for dirty martinis. And really, why would you buy vinegar and throw out your pickle juice? A good thing to do is keep a jumbo jar or two in your fridge and just keep adding leftover juice to it. That way when you have fruits or veggies that you know will go bad before you can use them, chop them up and throw them in the jar. They won’t make real pickles but they’ll last until you use them.