The Original Angry Birds has been marked to Free by Rovio Entertainment Ltd. Normally, Angry Birds is a $0.99 cent download. The company has also updated the app with 15 new levels, marking the first update in the app in a long while. Upon updating it, they also released the game to the public for free download, although no timeframe has been specified for this giveaway.
You can download the original Angry Birds game from the Apple iTunes store at: