There are always promotions going on with the App Store, whether it be directly through the store or another site offering it. Today there are 2 great games that you can pick up for free. The first is Angry Birds Space, which has been #1 in 116 countries and has been downloaded over a 100 million times. The next game that is been offered for free through IGN is Minigore 2 which received a 9.1 on IGN. The final App that is free, is a great weather App that has a really clean and simply to use UI, it comes highly recommend by my friend Josh Erickson.
This is being featured free on iTunes as App of the Week, here is a direct link.