I say "NO! Thank YOU!"
And then mutter "Rude prick/sod/git/bastard" as appropriate.
( Roota zweeeeeoooooowm, Fri 11 Feb 2011, 14:27, 2 replies, latest was 15 years ago)

I grab them by the scruff of their neck
throw them back out the door, then grab them again and drag them halfway through the door and slam it repeatedly on their faces.
(Bazongaloid, Fri 11 Feb 2011, 14:33, Reply)

I'd like to do that

( Roota zweeeeeoooooowm, Fri 11 Feb 2011, 14:38, Reply)

How many times have you realised they were mute after you've done that?

(PsychoChomp, Fri 11 Feb 2011, 14:39, Reply)

..whilst dressed as Rastamouse.

( Monty Boyce, My cheese game is strong, Fri 11 Feb 2011, 14:50, Reply)

Christ I'd love to have the balls to do this

(Reverend Fister "a disciplined fuckwit", Fri 11 Feb 2011, 14:52, Reply)

Yeah I go "you're welcome" really loudly.
And if they're smaller than me follow it up with "you cunt".
(Barry from Eastenders is, despite the words written above, not a woman, Fri 11 Feb 2011, 14:44, Reply)

my grandma used to do that
not the swearing bit, clearly. but she would hold the door open for people and then say "THANK YOU" really loudly if they ignored her. mortifying.

mind you, better than my friend's grandma, who, when asked if she wanted any watermelon at sainsburys, said very loudly, "good lord no. i always think you need to have a mouth like a n****r to eat one of those things." cringe.
( rachelswipe with a fork, Fri 11 Feb 2011, 14:48, Reply)

On bad days I have been known to do this
although I say 'you're welcome' in a really pointed manner instead. It's so passive aggressive, but meh, not saying thankyou is so rude.
(berk, Fri 11 Feb 2011, 14:52, Reply)