I'd say this machine is rather useless, which is exactly why it fulfills my expectations.

Really works. Very cute, and came with a neat little leather bag,

Such a fun little project. It really gets going too!
Awesome to teach kids (of all ages) about the dynamics involved.
Science can be so interesting.

Well made item-- the pieces fit together tightly.

Very well made demonstration of a very interesting physics anomaly.
Everyone I have showed this to are amazed, but they understand once explained.

Everything went really well. And tehre is very goot and immediate support.
Thank you!!

I've had these for probably 15 years. I wear it like a pin on my jacket with the separate magnets on the back holding it in place. Whenever someone asks about it (which is often) I have fun showing them the peculiarities of its attraction. One thing Tim doesn't mention is that when the two separate magnets are flipped they will stick to the larger ring if you bring them close but be repelled if you move them a bit farther away -- another bit of anomalous magnetic charm.

I've been assembling at my office for 2 days. In between patients. So much fun. Easy to follow instructions. A must have and a great gift for any dentist. I love it.

Really good. I am using it to model the bonding in hydrogen, H2. Actually, it better models the bonding in the [H2]+ ion, the simplest molecular ion.
The two positive nuclei in H2 repel each other (like the two big magnets), but the two positive ions are attracted to the electron(s), the small magnets. In H2 the bond length, 72pm, is a balance between the attractive and repulsive forces... just like in the inverter magnet.
Excellent!

It became one of my favourites gadgets from the very first moment I received.

I'm a big fan of tops, but this is something new. A very clever and mesmerizing design. The build quality is top notch. Everything machined to perfection. A real museum quality piece, but one meant to be enjoyed hands-on.

Wonderful Vortex / what a treat

This is such a gorgeous piece of kinetic art. So easy to get lost in the swirling beauty. The magnet is a fun addition too. Top quality material and workmanship.

Wonderful.

Entrancing presentation, most fascinating collection of boxes. Much food for thought...