PlayStation Now is a streaming rental service available on the PlayStation Vita, the PlayStation TV, the PlayStation 3, the PlayStation 4, and select Sony televisions. It is currently in open beta and the service is only available to most of the U.S.A and Canada.
In order to access the service, open the PlayStation Store and search for an download "PLAYSTATION™ NOW OPEN BETA."
The user must pass a connection test before they are able to access the service; Sony suggests a "steady broadband connection greater than 5Mbps." Once passing the test, the user can then rent games. Games can be rented for four hours, seven days, thirty days, and ninety days. The pricing differs from game to game, with the publishers and developers ultimately decidicing the rental duration and the pricing.
The rental does not begin immediately, but when you boot the game. The rental expires if you do not boot the game within thirty days.