- The Poly PagesAndrew Clarke's wonderful site with good graphics and information to match. If it starts with 'poly' you can find it here, in english, french, german and italian.
- KadonA commecial site, run by people with heart for their crafts and products.
- Tiling & PackingTorsten Sillke's site is a good place to start in the world of polycubes, polyspheres and tilings. Many useful links to sites in english, german and dutch. The emphasis is on the math rather than the handling of actual puzzles.
- Polyominoes Home PageKevin Gong's Polyominoes 7.0 program is available for Mac OS Classic, Mac OS X, and Windows.
- The Puzzling World of Polyhedral DissectionsStewart Coffin's famous book put online by John Rausch.
- Chinese Interlocking Burr PuzzlesTraditional Chinese interlocking burr puzzles and burr constructions.
- SOMAIf you're interested in Piet Hein's SOMA cube, Thorleif Bundgaard's site is the place to go.
- Rob's Puzzle PageA host of beautiful interlocking puzzles.
- Erich's Packing CenterErich Friedman is packing squares, triangles, circles and a lot of other stuff, some with animations.
- Convex PentagonsThe 14 different types of convex pentagons that tile the plane.
- Jigsaw Puzzles with Pieces of Unknown OrientationAt the borderline between jigsaw and pattern recognition.
- Puzzle PicnicA place to solve puzzles and relax, but also a place where puzzle solvers and puzzle makers meet, entertain and challenge one another.
- MathPuzzle.comThe puzzling weblog of recreational mathematics.
- Math RiddlesAnother puzzling website of recreational mathematics.
- Puzzles, Games, and Gift Ideas for All AgesA commercial site, but interesting.