Thank goodness it's payday; I've managed to resist buying games in the Steam Summer Sale for most of this week but I'm snagging Civilization V and Driver: San Francisco which are both reduced by 75%. Also on sale for 75% off are the rather good Deus Ex: Human Revolution and Dungeon Defenders.
GOG.com has the entire Kalypso range of games reduced to half price, including some classic strategy franchises such as Stronghold, Port Royale, and Tropico. Amazon.com has got Sniper Elite V2 for $14.99, a reduction of 70%, just in case you missed it in yesterday's Steam Daily Deals.
Elsewhere this weekend, GamersGate has focused on the Anno strategy franchise, reducing Anno 1404 by 70% and Anno 2070 by 60%. As always, post your PC weekend deals in the comments below as they're much appreciated.