A beer called mephistopheles stout, out of Avery I think.
It tasted like a mix of 4 day old coffe and used motor oil and 16% abv. It was the most fowl thing I have every ingested. If there was a such a thing as a beer monster. A big bad burly monster made of beer, and one morning he got up and took a dump, I believe it would taste like that.