If Batman: Arkham Origins and/or Battlefield 4 haven't already claimed your weekend, Steam and its brethren would like you to know that Torchlight II, Natural Selection 2, Saints Row IV, Far Cry 3, Metro: Last Light, The Walking Dead, The Witcher 2, Grid 2, Borderlands 2 and other noteworthy titles are currently available at a discount. Meanwhile, the Humble Weekly Sale offers 10 games by Team 17 (namely Worms and Alien Breed releases) for as little as $6.

Steam
87 Torchlight II $6.79 (66% off)
75 Magicka Collection $8.74 (75% off)
82 Natural Selection 2 $6.24 (75% off)
76 Earth 2150 Trilogy $3.49 (50% off)
77  Killing Floor $4.99 (75% off)
Tripwire Interactive Bundle $24.99 (75% off)
Guncraft $7.49 (50% off)
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Amazon Digital
82 Saints Row IV $29.99 (40% off + free Volition Comics Pack)
Vampire: The Masquerade: Bloodlines $4.99 (75% off)
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GamersGate
88  Far Cry 3 $14.98 (79% off)
83  Metro: Last Light $20.00 (50% off)
79 Hitman: Absolution $8.50 (66% off)
88 The Walking Dead $6.24 (75% off)
80 Sleeping Dogs $8.50 (66% off)
90 The Witcher 2 $7.98 (60% off)
66 Sniper Elite V2 Collection $12.49 (75% off)
Legacy of Kain Collection $6.25 (75% off)
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GameFly
68 C&C: The Ultimate Collection $8.99 (55% off)
88 Civ V + XCOM: Enemy Unknown $23.79 (66% off)
78 Tropico 4 Collector's Bundle $9.99 (75% off)
69 Q.U.B.E. $4.99 (50% off)
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Green Man Gaming
78 Grid 2 $24.99 (50% off)
75% off Eve starter packs
20% off select titles via "GMG20-P6Y1F-KC19F"
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Get Games
87 Borderlands 2 $10.19 (66% off)
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GOG
60% off Ubisoft titles