Θ Games: Puzzles: Brain

Site list:

My Days Are Numbered An article by Seth Stevenson offering a brief overview of Sudoku.
Sudoku.com Includes an overview of how Sudoku is solved, a monthly contest and a downloadable Sudoku game. Also includes a kids section and discussion forums.
Sudoku Online Includes Sudoku tips and strategies as well as a downloadable game and a 3D Sudoku puzzle.
Wikipedia: Sudoku An encyclopedia entry describing the rules, history, strategies and variants of Sudoku. Notes that these are a type of "latin square" which have been analyzed since ancient times.
Sudoku Fun Puzzles A website representation of Sudoku, the broad sheet newspaper puzzle imported from Japan. Leaderboard lets players compare completion times.
Maths Is Fun Offers a number of applications and solvers for a variety of platforms. Also offers custom puzzles.
The Guardian: Sudoku fever grips UK newspaper readers By Stephen Brook. Article covers how the UK craze got started.
Minimum Sudoku A project collecting Sudoku with the smallest number of givens that are still uniquely solvable. Offers the puzzle for download in text format.
SudokusWeb.com Free daily printable Sudokus. Also offers history, rules, and solving techniques. [English/Spanish/French/Catalan/German/Portuguese]
Sudoku Addict Offers printable grids and solution walkthroughs.
Sudoku enumeration Several programs in different languages for analyzing possible Sudoku combinations.
Sudoku Master Free daily grids that can be printed. Also offers solution and archive.
Sudoku-san Free daily puzzles with four difficulty levels. Also offers a solving assistant and downloadable e-book collections for purchase.
Information For Beginners Collection of printable grids, ordered by difficulty level. Solutions provided. Includes rules and solving methods.
Simple Sudoku Solver JavaScript brute force solver.
The Times Articles and puzzles from The Times (London).
Solving Sudoku Step by step guide to solving sudoku puzzles. Goes from basic to advanced techniques.
Christiaan Olie Personal page describing Sudoku, rules, strategies, and offering puzzles to print. [Dutch/English]
Sudoku Place Offers daily puzzle in PDF format. Includes archive, FAQ, and a "dozen" variant.
Sudoku Puzzles Offers four difficulty levels. The puzzles can be solved online or downloaded as a PDF file. [English/German/French/Spanish/Dutch/Portuguese/Italian]
The Sudoku Grandmaster Self-styled Grandmaster offers tips on life as Sudoku, humorous claims of achievement, and a daily puzzle.
Daily SuDoku Offers daily printable puzzles of varying difficulties, including Sudoku for Kids. Also offers archive of past puzzles, tool for rendering custom puzzles, FAQ, and books for purchase.
Universal Press Syndicate Offers monochrome and color grids and variations for online and print syndication. Information on syndication as well as an interview with creator David Bodycombe.
Sudoku Helper Free online helper application. Shows options for each square, and allows backtrack, restart, or save.
Sudoku Online Solver from friko.net Free online generator, solver, and helper. [English/French/Spanish/Polish]
Daily Sudoku Offers a different printable puzzle each day. Also includes solutions and FAQ.
Grant Gibson Offers syndicated puzzles for websites as well as print publications.
Sudoku Free daily puzzle with solution. Includes archive of past puzzles.
Yosmany.net Offers HTML to add a JavaScript-based puzzle to any site. [English/Spanish]
Fundoku Randomly generated puzzles at three difficulty levels.
Prize Sudoku Offers competitions for prizes. Traditional Sudoku, Godoku (letters) and Super Sudoku (16x16).
Puzzle Bus Offers a daily puzzle, books, software, and related merchandise. Also offers puzzles for syndication.
Gaby Vanhegan Daily and random puzzles at six difficulty levels, Flash and JavaScript solvers, solving techniques and glossary of terms.
9x9, 6x6 and Samurai Sudoku Offers classic Sudoku and variants, as well as an online solver.
Sudoku Provides sudoku puzzles in easy, medium and hard levels with their solutions. Also provides facility for daily email sudoku newsletter.
Sudoku Madness Seven days of daily puzzles.
Flying Frog Consultancy This web page describes a 19-line (769-byte) OCaml program that solves Sudoku puzzles.
SuDokuMate SuDokuMate is a SuDoku Helper (not a Solver) that replaces pencil and paper to aid solving.
World Sudoku Championship Information on the 2006 World Sudoku Championship held in Italy. Includes background information, events, results and FAQ. [English, Italian]
The Heebie Su Doku Site Offers a glossary of terms, links to puzzles and variants, and tips for solving.
Solve My Sudoku Solves puzzles based on inputted information.
Knight Features Publishing syndicate in the UK and Ireland. Offers several variations, including classic, colour, kids, and Sudoku Word.
Scanraid LTD Search Technologies Sudoku Solver by Andrew Stuart. Shows the logic behind solving sample games square by square.
Sudoweb Free daily puzzles with five difficulty levels. Also offers printable e-book.
Play Sudoku Flash version of the Sudoku game. Also offers solution.
Sudoku History, instructions, variants and puzzles in four difficulty levels (PDF format). [German/French/English/Spanish/Italian]
Sudoku Puzzles Free daily puzzles with five difficulty levels with their solutions. Also offers guide to solve Sudoku puzzles.