The Oddworld series is just the best, and this week PlayStation Plus members get Oddworld: Munch's Oddysee HD for free on the PlayStation 3. Otherwise the game is only $9.99.
PlayStation owners also have a new pile of discounts awaiting them through the Summer Blast promotion. 18 games are on sale, with notable titles including Just Cause 2, Prince of Persia Classic Trilogy HD, and Alice: Madness Returns all discounted. PlayStation Blog has the full breakdown of titles on sale with prices.