Top ten things that annoy me about fanfiction.net:

1. People who say, "I SUCK AT SUmARRIEES!!!!!!  JUST ReAD!!!!!!!!!!!!!!!!!!!!!!!!!!!"
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5. People who thank everyone and their dog before the story
6. People who talk to their muses
7. People who do not have their fics beta read, or, it seems, even read them over before they post.
8. People who peg for reviews, and threaten not to write another chapter if they do not get a certain number.
9. People who beg for reviews
10. Mary-Sue's