Along with free weekend access to Insurgency on Steam, Origin has a free copy of Wing Commander 3: Heart of the Tiger as well as access to Battlefield 4 for a week and a 48-hour trial for Kingdoms of Amalur: Reckoning. Freebies aside, Steam offers half off Saints Row and Warhammer titles, GameStop has Need for Speed: Rivals for $14 and the Crysis Trilogy for $20, GTA IV is $5 at GamersGate, Metro: Last Light Complete is $10 at GameFly, GMG has The Walking Dead for $5 and Borderlands 2 for $6.79, and Get Games offers 75% off Codemasters racing titles.

Steam
82 Saints Row IV $9.99 (50% off)
74 State of Decay $6.79 (50% off)
77 Insurgency $7.49 (50% off)
82 Saints Row Franchise Pack $27.49 (50% off)
86 Warhammer 40k: Dawn of War II Grand Master $27.19
75 Warhammer 40k: Space Marine Collection $14.99 (75% off)
72 Blood Bowl: Chaos Edition $7.49 (75% off)
75 Two Worlds Collection $7.99 (80% off)
75 Strike Vector $4.79 (60% off)
87 Papers, Please $4.99 (50% off)
Rochard $1.62 (81% off)
R.I.P.D.: The Game $4.99
StarForge $4.99 (75% off)
Meridian4 Complete Pack $50.00 (75% off)
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Amazon Digital
SteamWorld Dig $4.99 (50% off)
TopWare RPG Collection $5.99 (90% off)
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GameStop
90 Dragon Age Origins: Ultimate Edition $5.99 (80% off)
92  Sid Meier's Civilization V $7.49 (75% off)
78 Dead Space 3 $4.99 (75% off)
71 Alice: Madness Returns Complete $4.97 (83% off)
78 Crysis Trilogy $19.99 (60% off)
85 Need for Speed: Most Wanted $4.99 (75% off)
80 Need for Speed: Rivals $13.99 (65% off)
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GamersGate
73 Warlock: Master of the Arcane Collection $7.50 (75% off)
40 Montagues Mount $2.00 (80% off)
77 Rome Total War Collection $3.25 (75% off)
80 Risen Franchise Pack $8.00 (80% off)
88 Grand Theft Auto IV $5.00 (75% off)
Grand Theft Auto Trilogy $6.00 (80% off)
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GameFly
83 Metro: Last Light Complete Edition $9.99 (50% off)
79 Metro 2033 $2.99 (80% off)
74 Dead Island Franchise Pack $11.99 (60% off)
82 Saints Row IV $11.99 (40% off)
Sacred 2 Gold $4.99 (75% off)
Jane's Advanced Strike Fighters $2.49 (75% off)
Killer is Dead - Nightmare Edition $11.99 (40% off)
20% off select titles via "AUG20OFF"
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Green Man Gaming
88 Empire: Total War $4.99 (75% off)
81 C&C: Red Alert 3 $4.99 (75% off)
88 Left 4 Dead 2 $4.99 (75% off)
88 The Walking Dead $4.99 (80% off)
87 Borderlands 2 $6.79 (66% off)
88 XCOM: Enemy Unknown $7.49 (75% off)
88 F.E.A.R. $2.49 (75% off)
84 75% off Eve titles
Sid Meier's Pirates! $2.49 (75% off)
66% off Crusader Kings titles
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Get Games
66 Damnation $2.49 (75% off)
82 Darksiders $7.49 (75% off)
78  Darksiders II $7.49 (75% off)
86 Dirt 3 $6.24 (75% off)
70 Dirt: Showdown $7.49 (75% off)
84 F1 2010 $6.24 (75% off)
84 F1 2011 $7.49 (75% off)
82 F1 2012 $9.99 (75% off)
81 F1 2013 $12.49 (75% off)
78 Grid 2 $7.49 (75% off)
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Origin
Wing Commander 3: Heart of the Tiger $0.00 (free)

GOG
70% off assorted titles