VisibleBody (http://www.visiblebody.com)

Although the site is more about education than entertainment, its interactive design and 3-D controls make it a livelier model than most anything you'd find in a book. There's a "joystick" that can rotate the body along any axis as well as zoom in and out, so users can get a close-up of how a complex organ like the brain is organized, or use a wide angle to learn the names of the major bones in the skeletal system, for instance.

Students will find it useful for getting a hands-on, bigger picture perspective on anatomy concepts, and scientifically inclined teens and tweens may enjoy trying it out just for fun. One thing that would make the body even better: descriptions of what each part is and how it works.

Note: Visible Body requires Unity Web Player and Adobe Flash Player, both of which can be downloaded for free.