Steam's Summer Sale is behind us but the the Summer PC gaming discounts continues on, especially on Civilization titles. This weekend GMG launched a wave of discounts on this year's Civilization Beyond Earth, drops to only $15.40 - that's almost $5 cheaper than what was charged during Steam's Summer sale. There's also 81% discounts available on Civilization V, Civilization IV: Complete, and Civilization III: Complete (Civ V Complete is strangely missing).
In terms of retailer specific sale, Mac Game Store has their Summer Sale with daily deals and bundle offers refresh ever 24 hours. Most titles are Steam Play which means it'll work on both PC/Mac (and Linux for the occasional few). Over at Games Republic they've also fired up their "Summer Blockbuster Sale" with a decent lineup of AAA titles up to 75% off.
Until Saturday night, Microsoft's is throwing in a free game plus $50 store credit with the purchase of an Xbox One. It's probably the best offer you'll see this summer on Xbox One bundles. There are 15 options for the free game, including last Tuesday's release of Batman: Arkham Knight). For those wondering: no, the sexy Forza 6 Xbox One edition does not qualify under this promotion. You wish.
Last on the docket is a nice charity drive + giveaway running at Game Changer. If you donate $1+ to select charities, you'll receive a free Steam key of Deus Ex Director's Cut, courtesy of Square Enix and Game Changer. Full terms/detail in link above. (Please don't be a dick and abuse the charity drive).