Still haven't taken Borderlands 2 for a spin? Steam will let you fire it up free of charge through Sunday in addition to offering 50% off ($20 for the GotY edition). Meanwhile, BioShock Infinite is $10 at GamersGate and Green Man Gaming, Battlefield 4 is $40 at GameFly, Batman: Arkham Origins is $17 at Green Man Gaming, Far Cry 3 Deluxe Edition is $13 at Get Games, and the Humble Bundle has a handful of Sid Meier's games for a bargain ($15 for everything, including Civ V: Brave New World).

Steam
88 Borderlands 2 GotY $19.99 (50% off)
82 Outlast $9.99 (50% off)
66 Dungeons Gold $7.49 (75% off)
83  AI War Collection $4.24 (75% off)
Darkfall Unholy Wars $9.99 (75% off)
10,000,000 $0.99 (80% off)
Takedown: Red Sabre $1.49 (90% off)
Democracy 3 $12.49 (50% off)
7 Days to Die $23.44 (33% off)
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Amazon Digital
71 Strike Suit Zero $4.99 (75% off)
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GameStop
85 Dark Souls: Prepare To Die Edition $15.0 (50% off)
43 Star Trek $7.50 (75% off)
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GamersGate
92 BioShock Infinite $9.88 (75% off)
77 Total War Rome II $29.98 (50% off)
72 The Cave $3.75 (75% off)
64 Alpha Protocol $3.74 (75% off)
67 Aliens vs. Predator Collection $6.00 (75% off)
Viking: Battle for Asgard $3.75 (75% off)
Typing of the Dead: Overkill $10.00 (60% off)
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GameFly
81 Lego Marvel Super Heroes $9.99 (67% off)
82  Battlefield 4 $39.99 (33% off)
Battlefield 2 Complete Collection $4.99 (75% off)
Insanely Twisted Shadow Planet $3.75 (75% off)
20% off select titles via "FEB20OFF"
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Green Man Gaming
69 The Bureau: XCOM Declassified $7.49 (75% off)
73 Batman: Arkham Origins $16.99 (66% off)
64 Alien Rage Unlimited $4.99 (75% off)
92  BioShock Infinite $10.19 (66% off)
Sniper Ghost Warrior 2 $7.49 (75% off)
Injustice Gods Among Us $12.49 (75% off)
20% off via "PH4V4F-33PTVI-5HXNWG"
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Get Games
88 Far Cry 3 Deluxe Edition $13.19 (67% off)
89 Assassin's Creed II Deluxe Edition $4.99 (75% off)
80 Sleeping Dogs $4.99 (75% off)
90 Batman: Arkham City GotY $7.49 (75% off)
81 Company of Heroes 2 $13.59 (66% off)
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GOG
70% off Topware titles