People who try to use characters without knowing what names of said characters are. I once saw a fic that had 'Minato Yondaime' as one of the lead characters.
Horrible controls, horrible graphics, every soldier looks the same and the AI is ridiculously stupid. I only bought it because it was in the bargain bin.
I have to agree with the above. I cant stand it when people don't bother checking for mistakes. it also annoying when people write entire stories like this. its not that hard to hit shift and put in some capital letters.
I also hate stories where Naruto has some long lost brother or sister etc.
I recently saw a mixture of all my hates in one fic. The summary said something along the lines of 'a relatif of naruto's mom takes Naruto away from konoha after 12 years Naruto returns to konoha'.