I've noticed Sudoku has been quite popular lately. It's been appearing on newspapers, and my dad spends some of his leisure time exercising the gray cells with these numeric puzzles. Don't know what Sudoku is? As usual Wikipedia pulls through, providing an article on everything you need to know about Sudoku.

Turns out Sudoku's current popularity may be because of its availability on mobiles. Windows Mobile users might wanna check out Resco Sudoku. If the name Resco sounds familiar, they're also the company that came out with the famous Resco Explorer. The game boasts Smartphone and Pocket PC versions, for a discounted price of $11.96.

Resco also has a version for the Palm OS, also for $11.96. You can download all editions of the game for free, and enjoy a 14-day trial before purchase is required.