FEZ has been a game I dived into during the Autumn sale, its most likely on Steam now for less that $4 if my exchange rate is correct. A good single-player hour-killing puzzle-solving game which does the Indie genre proud.
Of course DayZ the Standalone game is currently in Alpha so I haven't purchased it, but if it gets caught up in the sales I'll think twice about it.
Any games you can recommend?