It's a big week for DLC on the PlayStation Store, with Mass Effect 3 Omega and Battlefield 3 (Premium) Aftermath hogging the limelight.
Remember than you'll need to be a Battlefield 3 Premium member to access Aftermath this week.
Also on the store are full downloadable versions of Ace Combat: Assault Horizon and Ratchet & Clank: QForce, the latter also granting you a copy for the PS Vita version when it releases in January. There's a LEGO The Lord of the Rings demo, plus Travel Bug is released for PS Vita.
A SEGA sale, featuring Jet Set Radio and Nights into Dreams, may also be of interest.
Source: EU PlayStation Blog