I've heard Martin do this a few times, and it's probably the funniest version I've heard. I do it sometimes too, and mine is similar to Martin's, although it's probably not quite the same. Here's my version:

RINDERCELLA – a Lisdexic Tairy Fale

Once upon a time, in a far away listening gland, there lived a geautiful birl, a shitty preila, and her name was Rindercella. Now Rindercella lived with her mugly other and two sad blisters. They beated her tradly - they made her dosh the wishes, bub the scrath, and flop the moors with a boapy sucket.

Now in that same coreign fountry, there lived a pransome hince, and he was a pretty fart smeller. One day the ling of the kand decided to have a bancy fall – a bagic mall, where his son, the pransome hince, could meet all the pralented and titty ladies of the land. You see, the pransome hince was sitty prick of seeing bingle.

Poor Rindercella could not bo to the gall, because all she had to wear were some old rirty dags. The night of the ball came, and Rindercella helped the sugly isters nowder their poses and tit into their fight dresses. She was sad because she couldn't go. She had to stay home and prepare tomorrow's roast because the bleaver was cu... er, the cleaver was blunt. So she just cat down and shried.. All alone, a tiny cheer scribbled down her teak making a rice nipple in the woapy sawter.

She was a kitten there a shrien, when all of a sudden, there came a FLINDING BLASH! and there stood - ger hairy fodmother! "Weep your ceasing!" she tharmingly chundered, "For I shall make you a tragic mess, and you shall bo to the gall!" She waved her wagic mand...and all of a sudden there appeared before her, a cig boach and hix white sorces to take her to the bancy fall. But now she said to Rindercella, "Rindercella, you must be home before nidmight, or I shall purn you into a tumpkin!" So Rindercella went to the bancy fall.

In the rall boom where wankers burled with their double-wind chives, the pransome hince was watching Rindercella from behind a widden hindow. "Who is this geautiful birl, this shitty preila? I must deserve every rance for her!" So they nanced all dight - until nidmight...and they lell in fove. As she and the prince chived and jaffled, Rindercella almost forgot ger hairy fodmother's pew farting whiny turds (that's few parting tiny words!) "At the stroke of nidmight, your fining white outshit will turn to rirty dags, so don't lolly dangler!"

Suddenly, the clock struck nidmnight! Rindercella blest her crutch and staced down the rairs, but as she beached the rottom, she slopped her dripper! "Bum cack! Bum cack!" cried the pransome hince, "You've slopped your dripper!" but she needed him hot.

The next day, the pransome hince went all over the coreign fountry looking for the geautiful birl who had slopped her dripper. He said "I must marry the gritty pearl, the shitty preila, whose fainty doot will shit in this farticular poo!"

When he came to Rindercella's house, he tried the slipper on Rindercella's mugly other...and it fidn't dit. He tried it on the two sickly ushers...and it fidn't dit. He tried it on Rindercella...and it fid dit! It was exactly the sight rize! The next day, Rindercella and the pransome hince were married and they lived everly after happens!

Now, the storal of the mory is this: If you go to a bancy fall, and you want a pransome hince to lall in fove with you...

DON'T FORGET TO SLOP YOUR DRIPPER!