Source: John Truby, Raindance Web Article
Paranormal Activity isn't a great film. But it is a brilliant indie filmmaking strategy. In my article "10 Story Techniques You Must Use to Sell Your Script" (see below) I state that "if you're writing a screenplay for an indie film, write horror, thriller, or love." Horror is the most consistently popular genre around the world after myth. But unlike the epic-scale myth, horror can be made for very little money.