Magnetic Newtons Cradle

This magnetic version fo Newton's cradle is no longer in production, but somtimes found on ebay:
From eBay: Search NOW: Magnetic Newon's Cradle

Here are some nice versions of the classic Newton's Cradle 
and here is a nice Magnetic Replusion Demonstration

Magnetic Newton's Cradle: the famous collision demonstration reimagined with opposing magnets as the pendulum weights- shown here in two modes of operation. Initially the collision pattern looks similar to the traditional colliding spheres version but quickly goes chaotic- the magnetic field of each weight interacts with all the other magnets simultaneously making the system nonlinear. A 1990s desk toy by Fascinations- sadly no longer in production. 

Newtons Yo-Yo

Get a set here: 
From Educational Innovations: BUY NOW Newton's Yoyo 

Newton Yo Yo: Newton's 3rd Law states that action force equals opposite reaction force- the the green and yellow spheres have equal mass, so the forces of the collision provide accelerations that are equal and opposite such that the spheres trade places.