Sony is revisiting its "Spend $50 on PlayStation Network, get $10 back" deal and it starts right now through October 29, 2013. Try to pace yourself!
Up to $100 can be earned using your Sony Entertainment Network Wallet and in addition to games, DLC, and the like qualifying, things like PlayStation Plus memberships and digital pre-orders are also valid for the promotion.
Using this offer, you could actually score a current-gen version of games like Call of Duty: Ghosts or Battlefield 4 and then upgrade to next-gen for free using that $10 credit. Or not. There's surely some PSN-only titles that you've been meaning to get for a while now.