Place bulbs on the grid so that every empty square lights up.
When you're fed up with Sudoku and Kakuro, try MPS-LightUp. The aim is to 'Light Up' every empty square by placing bulbs on the grid. Each light bulb illuminates the square it is on, plus all squares in line with it horizontally or vertically. No bulb may illuminate another, and some squares must have a certain number of bulbs placed around them. Version 2.11 now includes puzzle scoring, which adds the incentive not to guess your way to the solution, and high scores to track your progress.
On first glance this looks easy... But it isn't!
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<p>Nowhere near as involved as Sudoku, but a great way to pass time.
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<p>Comes with an excellent tutorial, too.
Cons
Could do with some more 'incentive' to finish the puzzle without making any mistakes.
Summary
Another great casual puzzle
MartynCodemology
Pros
This is a great casual puzzle. It doesn't require the same level of thinking as Sudoku, but isn't as easy as it looks, and is strangely addictive!
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<p>As usual from LTUC, it's well implemented, intuitive, and a great addition to your desktop.