This game is way too addictive!!!!
It's called Chiken Invaders: Revenge of The Yolk (number 3 in the series)(and it's the special Xmas edition). http://www.interactionstudios.com/ci3/chickeninvaders3xmas.php
I bought tried both Chiken Invaders 1 and 2, and this one is the best. The game is basically Raiden (or something like it) with more levels and weapons. It has 4-way multiplayer capabilities and LAN capabilities too.
The Xmas edition is awsome (the chickens burst into missletoes and stars ;) )
Please choose this game. It costs 20 USD