This isn't on Steam but I remember someone hoping for a sale on it earlier in the thread:
Kingdoms of Amalur: Reckoning is on for $27.99 on the Gamestop store (used to be called Impulse).
http://impulsedriven.com/kareckoning
Steam still has it for $59.99 so this might be the best deal in awhile if you don't mind signing up for a new service.
Back on topic, I just had my most expensive day today:
The Witcher Enhanced Edition
The Witcher 2
Thief Gold Edition
Thief II The Metal Age
Krater
I was going to add Sins of a Solar Empire: Rebellion to that, but I'll wait. I spent a lot of money on the base game and the two earlier expansions, I'm not willing to throw down $30 to add on a few more features. Besides, with everything else I bought, it can wait.