Sudoku puzzles

Killer Sudoku Blogger - Blog Case Study: ProBlogger Blog Tips I have been very keen on Sudoku since November 2004, when the excellent Wayne Gould introduced the puzzle to the Times. Since then I have done one, leading up to two or three, puzzles a day, as well as investing in Wayne's online version of the game (randomly generate as many as you like at whatever difficulty level you like). Wayne also kindly supplies versions of his puzzle to us for Nurture, the Nature authors' magazine, and many other outlets besides, probably. Although many have leapt on the Sudoku bandwaggon since that day when Wayne visited the Times to see if the newspaper would be interested in it (see the newspaper's archives for several articles), the only version that I really like compared with the original is "killer" Sudoku. In this variant, one has aggregate boxes to fill in within the main grid, rather than individual boxes, but the principle is the same. When the killer Sudoku variant was first introduced, it was rather thin on the ground, so I searched the web to find some additional puzzles. The only reliable site I could find is Su-doku-net, which provides a new killer puzzle every day. The Times also now does the same, at first running hand-made killers from a Japanese company, but now running computer-generated ones under contract with a company called Puzzlemedia -- they are a lot harder than the hand-made ones, and I mean a lot. Now comes this post on Problogger from someone called DJApe (real name provided!). In it, he explains how he began his Sudoku blog, "the home of perfect sudoku" in his spare time, and how he now generates a good income from it. Good work -- though I thought his tactic of posting a puzzle that is impossible to solve to drive up his traffic a bit cruel on us poor bepuzzled. There is something particularly attractive about Sudoku. But I don't know why: I am not, generally speaking, that interested in puzzles. Before Sudoku, I was quite happy doing the daily Times 2 crossword on the way to or from work. Now I do the two Sudokus supplied as well, and if I have any time before getting to my destination, I complete the "polygon" puzzle (make as many words as you can from a limited number of letters, always including a central letter). I don't understand the appeal of these puzzles to someone like myself who doesn't buy puzzle magazines or have any urge to do other types of puzzle. In addition to Wayne's book collections, I do have a couple of books of Sudoku "spinoffs" in case the supply ever runs out. Having had a look at DJApe's site, and with the other links mentioned here, I don't think that is likely to happen.