Trigon

The diagrammatic shapes show a set of triangular dominoes made up from the numbers in the table. The number in the centre of each domino show the sum of the numbers on its edges. Where one domino meets another the numbers are the same, so in order to save writing it twice, a space has been left where they meet. By using logic, fill in the numbers around each triangular domino.If you register at http://www.trigonpuzzles.com/ you get a free e-book with puzzles.

HaniDoku

HaniDoku is another sudoku variation.

More Information and a daily puzzle are on

http://www.hanidoku.com/

Sudoku variants

Goto http://www.hexapuzzle.hu/sudokuvariants/ for these strange sudoku variants

There are samples and a 'how to solve' page

Great Music: Katie Melua

Futoshiki

You have a grid of squares, some of which contain numbers, less-than (<) and greater-than (>) signs. Can you complete the grid such that every row and column contains every number

More Futoshiki you find on

http://www.brainbashers.com/futoshiki.asp

http://futoshiki.justplayfreegames.com/

http://www.sudoku-puzzles.net/futoshiki_4x4.html

SquarO

The goal of SquarO is to find the circles to fill in black. In each square, you have a number between 0 and 4 which corresponds to the number of circles around that square that must be filled.

SquarO can be found on http://www.squaro.fr/en/play.htm

Link-a-pix

It's friday and that means new free puzzles on http://www.conceptispuzzles.com/

Some of these free puzzles you only find on this website. For example Link-a-pix

Link-a-Pix puzzle clues are provided in the form of same-number pairs which are scattered inside a grid. The purpose is to find which same-number should be paired with which, and then to connect them in such a way that the number of squares the connecting path passes through is equal to the value of the corresponding numbers (including the end-squares containing the numbers

For a online tutorial go to http://www.conceptispuzzles.com/online/tutorials/index.htm#lap