Here are a couple of possibilities, depending on what you consider "famous":
* "You're a bit of a prat, you know that?" This line from the *Order of the Phoenix* is a classic Ginny retort, showcasing her wit and confidence.
* "But you're not even a real person, you're just a—a—diary." This quote from *Chamber of Secrets* demonstrates Ginny's courage and defiance in the face of Voldemort's influence.
Ultimately, the "most famous" quote depends on personal preference, but these are two of Ginny Weasley's most iconic lines.