Coppernickel, the Invention by Wouter van Reek.

Coppernickel is reading a book about inventions, when he reaches the end, the final page is blank.  This inspires him to create his own invention.  He knows it should be simple and useful, so he decides to create a machine to help pick elderberries that are out of reach.  He starts small and simple, but his imagination grows bigger and bigger and so does his invention!  Soon it is covering the wall.  When his friend, Tungsten, pushes some of the drawing out of his way, the cogs of the machine begin to turn and Coppernickel finds himself caught up in a different way.  At the end, he begins again and ends up with a simple and useful solution.

Originally published in Dutch, this book has a distinct foreign feel that makes it all the more interesting.  The illustrations are humorous and dare I say, inventive?  The ever-growing invention of Coppernickel is very detailed, contrasting nicely with the rough style that the characters and setting are drawn in.  The text is equally successful, using short sentences that allow the illustrations themselves to tell most of the story. 

A great book about imagination and inventions, this book is appropriate for ages 4-6.