VS. 
This weekend sees some pretty good games get decent discounts: Heroes of Might and Magic V + Expansions, Dark Messiah of Might and Magic, and Zeno Clash. You can pick them up individually, or in packs. It looks like it may be cheaper to pick up Dark Messiah and the HM&M5 pack separately, rather than together in a single pack.
Whooooa. Alright, now this is a great deal. If you can read this, then you should probably pick this up. The Orange Box is currently on sale for $10. Yes, for half the price of TF2, you get TF2 + The rest of the Orange Box including Portal. The only people exempt from the previous statement are those who already own the Orange Box for PC. Here’s the breakdown:
Steam is known for having great weekend deals. This week it is the Greatest Indie Pack for $10 (75% off). The Greatest Indie Pack includes:
Together, for $10, is a great deal on these games. Eets is a great puzzle game (also available for the xbox 360), and Multiwinia is a multiplayer version of Darwinia. Trials 2 is a very frustrating (but fun) 2d motorcycle game involving the arrow keys and physics-based stunts.