Along with offering up to 85% off Devolver-published titles including Serious Sam, Hotline Miami and Foul Play, Steam has a combo deal with Call of Juarez Gunslinger and Far Cry 3 - Blood Dragon for $12.49 (both titles are usually $14.99 separately). Elsewhere, GamersGate has 50-75% off assorted racing franchises, GameFly's still celebrating Halloween with up to 75% off L4D2, Dead Island and other zombie shooters, while the latest Humble Bundle offers six WB titles including Batman: AA and AC GotY.

Steam
95 Portal Bundle $6.24 (75% off -- today only)
75 Serious Sam Complete Pack $14.24 (85% off)
81 Call of Juarez Gunslinger + Far Cry 3 - Blood Dragon $12.49 (50% off)
82  Hotline Miami $2.49 (75% off)
Foul Play $7.49 (50% off)
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Amazon Digital
88 Guild Wars 2 Heroic Edition $34.99 (30% off)
77 Payday 2 $19.99 (33% off)
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GamersGate
81 Grid $3.74 (75% off)
78  Grid 2 $24.98 (50% off)
65 Fuel $2.49 (75% off)
86 Dirt 3 $6.24 (75% off)
82 F1 2012 $6.25 (75% off)
86 TrackMania United Forever $14.98 (50% off)
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GameFly
88 Left 4 Dead 2 $4.99 (75% off)
75 Dead Island GotY $4.99 (75% off)
58  Dead Island Riptide $11.99 (60% off)
42 Aliens: Colonial Marines $4.99 (75% off)
77 Killing Floor $4.49 (75% off)
79 Dead Rising 2 $9.99 (50% off)
60 Resident Evil 6 $19.99 (50% off)
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Green Man Gaming
74 Red Orchestra 2: Heroes of Stalingrad $4.99 (75% off)
73  Cities in Motion Collection $12.49 (75% off)
The Showdown Effect $2.49 (75% off)
Aliens vs Predator Classic 2000 $1.24 (75% off)
75% off Europa titles
75% off Men of War titles
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Get Games
81 Company of Heroes 2 $40.19 (33% off -- British Legion and Veterans Affairs editions only)
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GOG
60% off Activision titles