Software

DKM Sudoku Online
Play online puzzles at one of four difficulty levels. Also includes a solver program and hints. Software for Pocket PC and Windows also available.
http://www.dkmsoftware.com/Sudoku/

Erational Sudoku Helper
Flash application to assist in solving puzzles by using basic scanning techniques. Download and source code available.
http://www.erational.org/software/sudoku/

Galford's Sudoku Solver
Allows step-by-step solutions and gameplay. [Windows]
http://members.aol.com/aunegl/Galfords-Sudoku-Solver.html

Simple Sudoku
Freeware puzzle creator for Windows.
http://angusj.com/sudoku/

Su Doku Master
Sudoku puzzle generator and solver software for Mac OS X.
http://www.groethe.org/sudoku/sudoku.html

Sudogo.com
Offers puzzles in PDF and mySQL formats for solving offline or building into custom applications. Also offers online puzzles with three difficulty levels and customizable look-and-feel. [Dutch/English]
http://www.sudogo.com/

Sudoko Solver by Logic
JavaScript-based solver which attempts to complete grids by logic. Includes step-by-step description as well as suggesting a single move. Offers challenge to find new logical methods for "unsolvable" puzzles.
http://www.sudokusolver.co.uk/

Sudoku Companion
Sudoku puzzle generator for Mac OS X.
http://www.verek.com/products/sudoku_companion/index.html

Sudoku Dragon
Shareware puzzle solver. Generate and solve puzzles, print out the grid for solving by hand, tips and tutorials with online discussion forums. [Windows XP/2000/Me/98]
http://www.sudokudragon.com

Sudoku Java Solver Applet by Klaas
Java-based brute force solver. Displays animation of solution. Solves pre-defined puzzle or allows the user to enter his or her own puzzles.
http://sudoku.klaas.nl/

Sudoku Sensei
Open source application which describes the logic used to solve a grid, rather than using a simple brute force solution. Includes source code and samples. [Windows 95/98/NT/2000/XP, Linux]
http://sourceforge.net/projects/sudoku-sensei/

Sudoku Solver
A free utility to solve and email Sudoku puzzles.
http://www.sudoku-solver.com

Sudoku Solver
.NET solving program. Either offers hints or solves entire puzzle.
http://www.sudokusolver.net

Sudoku Solver in Three Lines - Explained
Small bit of perl code that will generate a sudoku puzzle solution.
http://www.ecclestoad.co.uk/blog/2005/06/02/sudoku_solver_in_three_lines_explained.html

Sudoku-Help
Excel-based shareware helper application.
http://www.sudoku-help.com/

SudokuME
Open source Sudoku game for any Java enabled phone. Includes downloads, a game manual and user forums.
http://smmj.sourceforge.net/sudoku/

Super Doku
Sudoku game available for Motorola V400.
http://www.clickgamer.com/moreinfo.htm?pid=3117&section=J2ME&set_device=1465