Today, DirecTV began offering a free 4-day preview of premium movie channels from HBO and Cinemax. The preview, which includes both SD/HD versions of the channels, starts Friday, Sept. 6th and ends Monday, Sept. 9th. The preview gives DirecTV customers who aren’t subscribed to the channels a chance to catch the Season 4 premiere of HBO’s original series Boardwalk Empire on Sunday, Sept. 8 at 9:00 PM Eastern. Popular movies playing on HBO and Cinemax include Argo, Dark Shadows, Life of Pi, Les Misérables, The Dark Knight Rises, and The Matrix films. The HBO channel package is normally priced at $17.99 per month, while the Cinemax package costs $12.99 per month. HBO can be found on Channels 501-511, and Cinemax can be found on Channels 515-523.