I've tried Balot once and it doesn't taste much different than the smell.
I think the worst food I have seen was on No Reservations when Anthony Bordain went to Africa and was offered raw intestine cut right out of the water buffalo.
I have tried Brain but you have to be really careful with it as you can get really sick if you dont cook it properly.
"fried chicken anus" in china is pretty gross.
I think the one that takes the cake is "virgin boy eggs" from some area of China. Basicly they collect all of the pee from the urinals at the kids school and boil eggs in the pee.
http://en.wikipedia.org/wiki/Virgin_boy_egg