Try VideoSurf - a video search engine.
Movie Monitor: tracks the availability, quality and pricing of on-demand and streaming movies across the web's leading providers, including free movies.
FedFlix: A joint project of the National Technical Information Service and Public.Resource.Org, featuring movies of the United States Government free to use. Search by categories (Spirituality & Religion, for example).
Europa Film Treasure: A searchable, free archive for hundreds of European cinematographic works.
Internet Archive: Moving Images: Thousands of digital movies - from classic full-length films to daily alternative news broadcasts, to videos of every genre uploaded by Archive users. Many of these movies are available for download.