Math Toys

Hyperboloid Spinner
Available here:

From Amazon: BUY NOW
HypnoGizmo

From eBay: BUY NOW
HypnoGizmo
Pencil Hyperboloid
Choose your color and get one here:

From Etsy: BUY NOW
Hyperboloid Pencil Holder


don't forget a set of pencils:

From Amazon: BUY NOW
Colored Pencil Sets


Better yet- get some thermochromic color changing pencils!

From Educational Innovations: BUY NOW
Heat-Sensitive Pencils
Orbiforms
Latest orbiforms available here:

From Kickstarter: Order NOW
Orbiforms in Steel, Brass, or Copper
Shadow Stereographic Projection
These mathematical art objects are created by Henry Segerman and available here:

From Shapeways: BUY NOW
Mathematical Art


Wikipedia has a nice introduction to the math and applications of stereographic projection.
Cylinder Anamorphic Art
This image by István Orosz is available as a poster and as a puzzle:

From Amazon: BUY NOW
Mysterious Island Puzzle

From MathArtFun.com: BUY NOW
Mysterious Island Poster

Many books are available (with mirror cylinders) from Amazon: Anamorphic Art in Books
The d120
Get one here! Four colors to choose from.

From Amazon: BUY NOW
120 sided dice
Pythagorean Theorem Puzzle
Available here:

From Creative Crafthouse: BUY NOW
Pythagorean Puzzle
Dudeney's Dissection
Get this version here:

From Grand Illusions Ltd: Dudeney's Dissection
A nice wood version is available here:

From Etsy: BUY NOW
Dudeney's Dissection

See both Wikipedia and Wolfram MathWorld for more details on the history and math of this geometrical oddity.
Pentominoes
Get this set here:

From Etsy: BUY NOW
Pentominoes


Many versions available here:

From Amazon: BUY NOW
Pentominoes
Klein Bottle by Cliff Stoll
The best Klein Bottles are made by Cliff Stoll, astronomer, mathematician and artist. Every one-sided, zero volume bottle is packaged and shipped by Cliff himself. Get one today!

From ACME Klein Bottles: Buy NOW
Klein Bottles by Cliff Stoll


Wikipedia has great details on the Klien Bottle, and the amazing Cliff Stoll.
Tessellating Geckos
These laser cut hardwood geckos are available here:

From Etsy: BUY NOW
Tessellating Geckos
Rhombic Blocks Mathematical Puzzle
This beautifully made puzzle available here::

From Etsy: BUY NOW
Rhombic Blocks
the Hyperbola Clock
This amazing clock available here:

From Amazon: BUY NOW
Hyperbola Clock

From Amazon UK: BUY NOW
Hyperbola Clock
The Galton Board
Available here:

From Amazon: BUY NOW
The Galton Board
High Voltage Fractal in Wood
Amazing creations made here:

From Etsy store EngravedGrain: BUY NOW High Voltage Fractal
Logarithmic Spiral Gears
Amazing creations made here:

From Etsy: BUY NOW
Spiral Gear Set


Original 3D print available here:

From Shapeways: BUY NOW
Spiral Gear Set