One of the banes of my existence, at least when it comes to the Wallet and my limited free time is the Steam Winter Sale.  Mostly because I find old games that I had forgotten about for years on sale cheap (Geneforge Saga, Majesty HD anyone?) or new games that are very intriguing for, quite possibly, all the wrong reasons (Corporate Lifestyle Simulator).  In any case, take advantage of them while you can, and enjoy the memories (new or old) created by steep discounts on the games you love.