How can I turn excess wine into delicious wine vinegar at home?  For those who have done it, are there any useful tips to get the best results?   I do not have access to any "mother of vinegar" starter culture, and am not likely to spend money on it; however, I DO have a well-stocked home kitchen and a lot of patience.  Edit:  To be more specific about my questions   How long should it take to ferment, and when do I give up if it's not vinegary? Do I need to add sugar/water for low-sweetness or high-alcohol wines? How do I collect Mother of Vinegar for use in fresh batches?  
My accidental vinegar just happened, and I have been able to propagate it by pouring the last few teaspoons from one bottle into the next (after drinking half of the next bottle).   It goes pretty slow using an open bottle (too little circulation) but it does go. I open the bottle every day or so and swish the contents around. It takes about 1 weak to even start smelling vinegary, and circa one month to really develop.   I've been sticking with the same variety of wine and not trying to diddle the sugar content.  I still have not developed a mat-like mother, but there does seem to be a culture there. I'm on the fourth generation now. 