I've always held a fascination about magnets, the freakish strength of the truly powerful ones is amazing. Found a site where you can buy all things magnetic, up to the " so powerful they're stupid" sizes.

Also for sale...ferrofluid, seen above. This liquid has tiny magnetic spheres suspended in it, and forms wild and wonderful shapes when exposed to an outside magnetic field . Being tested for use in car shocks, where applying a variable current to ferrofluid "oil" inside could instantly change the ride characteristics of the car. Interesting research.

They also have magnetic rings. Why? I don't know.

UnitedNuclear