My four-year-old son wrote the following story. I think it has a nice Dexter and Computress Get Mandark feel to it.
Once upon a time there was a train
and it was red.
But the coal car was blue.
One day the red train
with the blue coal car was carrying boxcars and a caboose and a flat car.
And a car with wood on it.
It went on the tracks to the ding ding and the railroad crossing sign turned on! And all the ding dings turned on!
The train went to the city.
It went through the city and came out the other side.
Then it went inside a tunnel and turned on the lights so it could see where it was going.
Then it went to Disneyland and came out on the way back.
Then it turned into a rocket ship and flew into space and went to the moon.