favourite line from the books or movies

What would you say is your most favourite line from either the books or movies.....
From the books, mine is when they are all sitting around the table in the leaky cauldren an Percy wants to know why they are sending ministery cars to take them to the station, and fred and george says, "they are for you perce with little flags on them with HB on them,,,,,,for humungus bighead.
Brilliant.
And from the movies is when Hermione punches malfoy in the nose and calls him a foul loathsome little cockroach.
Bring it on.

.....and for this i honour him....... -dd
(the films, i ve never watched)

This is SO difficult. I really don't think it would be possible to choose just one quote from the books, or even from the movies.
One that comes to mind at the moment is from HPPS, that first Potions class.
"I can teach you how to bewitch the mind and ensnare the senses, how to bottle fame, brew glory, and even put a stopper in death."
Of course, in a classical Snape moment, he follows this line with something to the effect of "If you aren't the usual dunderheads I have to teach".

From the PoA movie, one of the really great lines original to the movie was a bit of comic relief they added with Ron and Harry, as Ron wakes up suddenly from a nightmare: "Spiders...the spiders...they want me to tap-dance. And I don't want to tap-dance!" Harry: "You tell those spiders, Ron." Ron: "Yeah, tell them...I'll tell them..."
And Ron, being Ron, falls promptly back to sleep. XD

One of my favorite lines is Hermione's " Oh well spotted ." when Ron tried to ask her to the ball .

I like the line about Voldermort running as fast as Snape when confronted with shampoo in book 7

when harry wins the match in PoA, when he wins in 1st and 2nd task in GoF, when sirius tells him to come and live with him in PoA, when fred, George and ron rescue harry from the muggles in CoS, when harry takes luna to the ball in tHBP, when bill marries fleur in DH, when harry wins the house cup in PS, and, and and and....like them all....

Dialogue btwn Harry and Ron GOF ~ Movie

H: "You're a right foul git , ya know that!"
R: "Really ? Anything else?"
H: "Yeah , keep away from me"
R: "Fine"

I love this because it seems REAL !
( NO PUN OR INUENDO MEANT in relation to anything going on HERE !...I just happen to be watching it again today!)

Well... mine isn't exactly a quote... it's an action written in the PoA book:
Hagrid hurries off with his face buried in his handkerchief.
Malfoy:"Have you ever seen anything quite as pathetic? And he's supposed to be our teacher!"
Harry and Ron both made furious moves towards Malfoy, but Hermione got there first-SMACK!