There are a few games that can turn even the most casual gamer's free time into an obsessive tweakfest. “;Angry Birds,”; by Rovio, is one such game.

The objective of this “;castle demolition”;-style game is to slingshot a group of birds, one by one, at a group of green pigs and their makeshift “;fortresses”; of shaped wood, glass and stone and knock out all the pigs before running out of birds.

While the idea seems somewhat brainless, the game-play requires a basic understanding of ballistics and physics to complete progressively more difficult levels. The pigs' fortresses get more complex (and silly) as the levels progress, but luckily, the birds also have specialty abilities to aid in the demolition of tougher structures, including bombs and speed boosts.

The graphics, animation and sound are presented well and in a hilarious fashion, with flying feathers and bruises accompanying the many crashes and booms.

“;Angry Birds”; is available for the iPhone as a free “;lite”; version with 12 levels and full version with 100-plus levels, as well as an HD version for the iPad.

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