I’d be very disappointed in your mum if she responded thusly. 
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Just because you’re paying you don’t get better service.
“Well, it’s too late to take it back now”
“Is that really the best post you could come up with?”
“Hmm. May we direct you instead to http://www.sesameworkshop.org/ ?”
pan
“Gee, another post! Just what I’ve always wanted.”
“Thank you for your post. Please wait in line for your validation”
“We are hamsters, super hamsters; we are running very fast.
We are working in the server; we are processing your post” (to the tune of We Are Sailing)
I would want a random response generator since all of the above are great.
Want fries with that?
Dear Poster,
Just watch as we eat your post, and log you out at random times (so you have to login again at least once). This will probably force you to compose that long-winded, bandwidth-wasting, server-straining essay yet again! But don’t worry, repetition and do-overs build character. Oh, and by the way, it’s too late to correct any typos (preview is your friend, remember)… unless you want a quadruple-post on your hands and on this board. Now, are you sure you really want to post that?
Love, the hamsters.
Personalized messages would be more interesting.
“Oh, it’s you again, scott evil. Posting AbFab trivia again? You win; no one cares. Posting about your sex life? You’re gonna inadvertently start a flamewar in the Pit. Flirting with yet another board crush? Get a room, boys. Posting about your various injuries? Just take another Percocet, dear, and step away from the computer. That is all.”
- s.e.
Every time you post, the Mods kill a hamster. Please, think of the hamsters!
Isn’t that redundant?
Thank you for your post. It has been added to your file, and the authorities will be in contact soon. Please wait by your computer for further instructions.
Somebody please open up the windows!
What was that stench?
Did YOU do that?!
OG SMASH!
Or better yet, as the network crunches on your silly post, the entire "Thank you for posting … " page should be this: http://www.hampsterdance2.com/stagedance.html
“Spam spam spam spam. Lovely spam! Wonderful
spam! Spam spa-a-a-a-a-am spam spa-a-a-a-a-am spam. Lovely spam! Lovely spam! Lovely spam! Lovely spam! Lovely spam! Spam spam spam spam!”
Dear Poster:
We regret to inform you that all available slots in threads about Topicare currently full. Please hold for an available slot.
::cheesy music::
Sir made the littlest hamster snort breast milk through its nose. Shall we be clever again? Hmmmn?