The Ten Writing Commandments
(in no particular order)
10) Thou shalt not use adverbs.
9) Thou shalt not begin a story with a dream sequence.
8) Thou shalt always 'show' and never 'tell'.
7) Thou shalt not use the word 'that'.
6) Thou shalt attend writers' workshops, conferences, and book fairs at every opportunity.
5) Thou shalt not have a character describe themselves by looking at their own reflection.
4) Thou shalt have many many many people critique your work before submitting.
3) Thou shalt never use cliches.
2) Thou shalt not have unsympathetic main characters.
1) Thou shalt take these commandments seriously.
Okay, so maybe that last one should say 'shalt not'. Unlike the biblical commandments, nothing is carved into stone here. Every one of these rules has been broken, and should be broken depending on what your story needs.
Or in the words of Neil Gaiman (whose wildly popular books are selling like hotcakes, btw): "Write your story as it needs to be written. Write it honestly, and tell it as best you can. I'm not sure that there are any other rules. Not ones that matter."
What are some rules you've heard about that you've broken? Better yet, tell me about some rules bestselling novelists have broken. Those are always fun. =oD
And tell me if I missed any commandments. Who knows, this could be like Mel Brooks' History of the World Part I:
"I bring you these fifteen... (crash)... ten... Ten Commandments!"