I call those punishment beers and I'll drink as much of it as I can stand to make myself do better next time. But I won't share it unless another brewer was involved with the catastrophe. Luckily it's only happened a few times. If it just tastes bad and is not too hoppy, I'll rack it to a carboy and either make malt vinegar or add brett and lambic blend bugs just to see what happens. I did turn a crappy porter into a fantastic sour porter.