One of the Angry Birds cheats in the game are the hidden golden eggs which can unlock additional levels. Here is where you can find the golden eggs.
Golden Egg Locations
Golden Egg #1: Watch the credits until the end and then tap the golden egg that appears at the end.
Golden Egg #2: After clicking Play when you go to the levels menu, begin tapping the sun.
Golden Egg #3: Click Pause during the game and watch the video of the white, egg-laying birds.
Golden Egg #4: Get the maximum amount of stars on the first three levels.
Golden Egg #5: Get the maximum amount of stars on the last two level sets.
Golden Egg #6: In level 1-8, tap the treasure chest.
Golden Egg #7: In level 2-2, destroy the beach ball.
Golden Egg #8: In level 4-7, pan all the way out so you can see the hidden yellow bird.
Golden Egg #9: In level 5-19, pan all the way out and tap the rocket.
Golden Egg #10: In level 6-14, there is balloon floating beneath the level of the platform on that right that all the pigs are on. Use the new Boomerang Bird in order to get it.
Golden Egg #11: On the 8th level set, go to the far right and keep pulling the screen to the left. A golden egg will eventually poke out. Keep pulling the screen until the eggs is completely uncovered and you will end up getting it.