Slowpoke Productions is the creator of the Randomly Oscillating Magnetic Pendulum (ROMP).

The ROMP is an addictive desktop toy that combines magnetic forces, gravity, and pendulum motion to create an endless variety of chaotic motions shaped by the magnetic landscapes you create.

You choose the arrangement of magnets on the ROMP's base to create fields through which the pendulum must swing. The complexity of the fields is limited only by your imagination.

Graphic created using Mathematica for Macintosh

Then simply let the pendulum loose and watch it dart and dodge through the fields!

History:

Originally crafted in the early 1990's from birdcage perches, shishkabob skewers, and the shell of a PC, the ROMP found its first admirers in the physics department at Bellevue Community College. The name was coined by the inventor's spouse for a college writing assignment in which the student had to author an explanation for a difficult-to-explain object.

After some design improvements, it was first offered for retail sale in Pacific NW science and nature stores in 1993 and has developed an eager and devoted following.

The ROMP is currently manufactured and sold under exclusive license by Hog Wild Toys.

Check out the action shots at ThinkGeek.com!

If you have to take it with you, here's how you can make a portable ROMP out of an Altoids tin.

And there are plenty of videos of the ROMP, similar mechanisms, and computer simulations with explanations and musings on YouTube.

There are more graphical and movie visualizations of the forces at work at the science store 4physics.com.

And no, there is no perpetual motion or anything of the sort at work here. See this article for a practical and common-sense debunking. The system is simply very efficient with very little loss in air friction or the strand of nylon used for the pivot. The pendulum is intentionally rigid which further reduces mechanical friction losses. This all makes the exchange of energy between gravitational potential energy, magnetic potential energy, and kinetic energy very efficient. In addition, we are accustomed to thinking of the total energy in a traditional pendulum as being related to how high the pendulum is lifted above its lowest point the swing. However, in a ROMP it's related to the lowest point in one of the attracting magnetic "wells" and given the strength of the ROMP's magnets (especially if stacked) that well can be quite deep and accelerate the pendulum to high peak speeds. We think it's the introduction of the added dimension of magnetically-induced and unexpected motions and the greater than expected total stored energy in the raised pendulum that make the ROMP's actions so seemingly energetic.

We're also avid Macintosh fans! Our closets are filled with a collection of vintage Macintosh computers ranging from the iconic all-in-one Mac 512K to more recent models.

We rescue Macintoshes from garage sales and thrift shops, lovingly restore them, and fill them with tons of great free software. These old machines may not handle the latest multimedia web pages, but for bulletproof, virusproof, unhackable simple web servers, and a word processing station, the Macintosh is unbeatable. And of course, the Macintosh is legendary for being a simple, reliable computer that requires virtually no maintenance for anyone from age 2 and up.

68K MLA visitors! I have tons of stuff here for sale. More will be added periodically. There are vintage CPUs, AppleTalk and Ethernet adaptors, cables, and more.