Strange attractors are fractals that arise from relatively simple math: they're generated by iterative systems, in which a formula applied to their own results over and over.  The resulting path, instead of forming a simple shape as you might expect from simple equations, skips around forever, slowly filling in a lacy fractal design.

Quaternion Julia sets have much in common with the more familiar 2D Julia sets, and indeed each contains a Julia set as its central cross-section.  More about the math is here, and of course there are many more online.
 

Quaternion Julia, 80mm glass cube – $72

Without illumination the crystal works best on a dark background.  It comes with clear rubber feet to avoid scratching your desk or mantel. On the left, this light base is a great way to light up your fractal! It's made of black Formica and has white LEDs that are cool, long-lasting and energy-efficient.  Bright enough for the office by day, or a brilliant nightlight. Light base – $20 I apologize, light bases are backordered until probably mid-January.  If you'd like to shop anyway, we won't delay the rest of your order to wait for a base (unless you ask), and when they come in we'll ship yours immediately at no extra cost. Thanks for your patience!

 

This attractor was generated by Nicolas Desprez using his excellent freeware: