The thing I hate most is the thing I program in most
Nothing's perfect and the more you get used to it the more you find to dislike. The only exception I've encountered is awk (NOT gawk, the one-true-awk) probably because it is incredibly simple and either does what you need or doesn't (in which case you have to use something else so don't grow to hate it.)
Putting "assembler" in the poll is just about as useful and informative as putting ASCII in there would have been. I program in ASCII all the time and it sucks.