Stinky tofu is sold on the street, and when I got to Shanghai, I thought it was one of the worst smells I had ever smelled. It smells like acidic body odor. It took me about a year to work up the courage to actually eat some of it. It actually is not that bad, and now that I've eaten it, the smell no longer bothers me. It's not something that I crave, but I'll eat it if someone buys it. The smell comes from the fermentation of the tofu, which is then deep-fried and served with chili sauce or a nondescript brown sauce. When buying from a street vendor, they will typically ask you how stinky you want your tofu, to which you should reply, "Extra stinky!" Gag.