Gadgetopia

The best place I found to play online is at Web Sudoku - really nice and easy interface. Some others are listed in the Wikipedia article though.

Are there three rows or nine? Are "rows" delimited by the light or dark lines in your graphic above?

Its 9x9, you want 1-9 in each of the 9 subregions and 1-9 in each row and column. The example above was advertised as difficult.

I'm hooked.

My favourite place to play online is SudokuHints.com. There's a new puzzle every day, and it can give you hints if you get stuck.

Just thought you might like to know that there is a new Sudoku program available for download at www.GoldstoneServices.co.uk

The full product includes 10,000 brand new puzzles; puzzle solver; design mode to create your own puzzles; print option - handy for journeys; puzzle checker to see if you have made any obvious mistakes; Auto Notes so you can see candidate numbers for each square at a glance.

The demo version includes 10 sample puzzles of varying degrees of difficulty so that you can try before you buy. The product is priced at £9.99 which is not bad when you consider that thats for 10,000 puzzles!!!

What a bunch of search engine spammers you all are. Web sudoku is laughably bad as is sudoku hints and goldstone are trying to flog an over prices bit of junk. Even Wayne Gould, the chap that introduced Sudoku outside of Japan, charges less than Goldstone for his software.

i was going to tell you all about this real cool sudoku website that i found but then i thought you might think like i was spamming. so if you want to know which website i found follow the links at this website and you will know when you have found it ;)

Theres a version for mobile phones at this site. http://www.sudokumobile.net

I like this one:

http://www.playonthego.com/sudoku

It has both a simple web based puzzle and solver and also a mobile version.

Thanks for the pointer. But I guess this highlights a problem with Wikipedia - dozens of Sudoku site developers have shoved their links into what has become a grand unmanaged list. So it's hard to know where to start but I did find decent puzzles on the Sudoku Addict, Web Sudoku and Brainbashers sites. Some of the others are awful!

Be sure to check out Wikipedia and Essential Links to SuDoku for a host of internet resources on Sudoku!

Goobix.com also has an online version of the Sudoku game with hundreds of available puzzles.

If you are looking for a Sudoku assistant for Mac then check Sudoku Companion.

We loved the game so much we decided to develop one ourselves: Sudoku Daily Games. This game is computer generated and there are several different levels with six new games to choose from every day. I read an interesting article about hand-made sudoku games versus computer generated games. The article is from Japanese Sudoku publisher Nikoli, and it outlines the beauty and art that go into a hand made puzzle. Keep in mind that Nikoli produces these hand-made puzzles (or are they hand made with computer assist?), but it's interesting all the same.

Fiendish Sudoku offers new puzzles every day at five difficulty levels, an extensive archive, hints and step-by-step solutions. It also has several printing options.

If you like a real challenge, there's Samurai Sudoku.

• KristinW