If you have money that's not on steam, I recommend getting The Humble Indie Bundle/ Humble Weekly Sale If you only have steam money, Saints Row The Third is on sale. I personally recommend that too, funny game (Not suitable for young children) If you're under the required age for that, Terraria and Worms: Reloaded-GOTY. Both are (Relatively) cheap. By the way, If Terraria and Worms costs more than $20, I'm British, so I haven't yet memorised exchange rates.