In special features of Sin City, Rodriguez says there’s lots of software to create similar greenscreen effects?

In the special features of Sin City: Recut and Extended, Robert Rodriguez mentioned that today there are lots of software you can use with a digital camera to create green-screen like affects. Does anyone know any programs? Preferrably fairly beginnerish and easy to use, and free or with a free trial. Thanks.
March 6th, 2010 by nickadmin 
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