the most awesome quote from harry potter and the deathly hallows (book 7), when mrs. weasley takes on bellatrix lestrange and kills her for trying to take on her only daughter, ginny. quite possibly the best/ most badass quote in the series.
An expression commonly used right before you walk away from a girl who won't stop bitching. It can also be used towards any person regardless of gender when you don't like their answer to your question (it is normally mumbled when used in this context).