One of the things I adore about the Japanese is their near-magical ability to transform, manipulate and just plain BUILD with paper. Take this person, for example, who has concocted mechanical paper models that move, including the astronomical models shown here. A delightful project for children and adults — download the printable PDFs here (zip file, 4.4 Mb. Thanks to Debbye for sending me all the files!) The instructions have lots of diagrams, so you should get by without a reading knowledge of Japanese. (I hope!)