The latest pair of PlayStation Mobile games to go free as part of Sony's Festive Giveaway are Fuel Tiracas -- which is reaction game described as a mix of Whack-A-Mole, Simon Says, and spinning plates (how does that even work?) -- Vlambeer's hit Super Crate Box.
Chances are you've played it by now as it's been a freeware release for so long on PC, but this specific handheld version of the tightly-designed arcade title is worth getting. I say that as someone who doesn't dislike Super Crate Box on iPhone. It's just not the same, though.
Venture to the PS Mobile section of the PS Vita store to find these free games, or download them for your PlayStation-certified mobile device of choice.
PlayStation Mobile Update: More Free Games This Week and Two New Releases [PlayStation Blog]