For those without an iPhone/iPad/iPod you can get a PC version for $5 in the form of a digital download.
I can't post links for some reason, but do a google search for angry birds pc
You download the trial version, then there will be an option in game to purchase the full game (digital format) and pay via the payment processor.
You get the registration key sent via e-mail..
Or if you use Google Chrome, you can get the game with a few levels as an add on.