NEW YORK (CNN/Money) - In an effort to cash in on Sudoku's massive popularity and prevent it from slipping from today's mainstream pastime to yesterday's bizarre craze, several companies are rolling out electronic and other new formats of the crossword-like numbers game, according to a report Friday.

Traditionally played with a piece of paper and pencil, several software companies are making versions for cell phones and PDA's like the ones made by Palm, the Wall Street Journal reported.

The Journal also said retailers such as the Discovery Store are making hand-held electronic versions, while Briarpatch Inc. is coming up with an old-fashioned Sudoku board game.

The game is even proliferating online, with several Web sites offering games for download. It is even appearing in math classes around the world, the Journal said. The game's popularity doesn't appear to be waning.

The article quoted one man who said he had to swear off the game for two months because he was playing it so much it was hurting his productivity. He now plays just once a week.

And British Airways recently issued a memo to its employees, the Journal said, reminding them that the game isn't to be played during take-off and landings.

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Can the popular Japanese number puzzle save newspapers or is it just a passing fad? Click here