Sibrecht Bouwstra, a Dutch student of Industrial Design, has published her design of a "Natural Animation Extension Pack for LEGO® MINDSTORMS":
"My goal was to create an actuator and brick that stimulate natural animation and are useful forAs you can see from the pdf document, Miss Bouwstra manufactured a custom motor that is much more silent than an original NXT motor and her own (flexible) parts from plastic and latex.
the creation of autonomous robots. Therefore, I explored with the creation of flexible bricks and a silent & small motor. The results and a practical documentation on how to create the bricks, can be found in the following link for those who are interested: [link]
I hope this information will be useful to you! A movie of the result can be found on [link] (Click on Gallery and than on the Lego brick.)"
Do not miss this!