Gearing up for Dead Island: Riptide's release on April 23, Amazon has discounted the first installment's game of the year edition to only $5 in addition to offering Borderlands 2 with its season pass for $25. Elsewhere, Steam offers 85% off and free access to Red Orchestra 2 (though it's a tad cheaper via the Humble Weekly Sale), GameFly has up to 75% off adventure titles including The Walking Dead, and GOG cuts up to 80% off D&D games.

Steam
74  Red Orchestra 2: Heroes of Stalingrad $2.99 (85% off + free weekend)
74  Red Orchestra Franchise Pack $5.24 (85% off)
86 Battlefield: Bad Company 2 $4.99 (75% off -- today only)
87 Torchlight II $9.99 (50% off)
77 Tripwire Interactive Bundle $8.99 (85% off)
90 DCS A-10C Warthog $19.99 (50% off)
Omerta - City of Gangsters $19.99 (50% off)
Kung Fu Strike - The Warrior's Rise $2.49 (75% off)
Altitude $2.49 (75% off)
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Amazon Digital
74 Dead Island GotY $4.99 (75% off)
87 Borderlands 2 + Season Pass $24.99 (72% off)
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GameStop
85 Eve Online Starter Pack $4.99 (75% off)
78 Victoria II $4.99 (75% off)
58 Gemini Wars $6.79 (66% off)
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GamersGate
78 Might & Magic: Heroes VI Gold Edition $20.00 (50% off)
71 Painkiller Complete Pack $18.00 (70% off)
78 Crazy Machines Ultimate Pack $20.00 (50% off)
66 Adventure 4 Pack $9.99 (75% off)
Fallen Enchantress $15.00 (50% off)
Euro Truck Simulator 2 $14.98 (50% off)
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GameFly
92 The Walking Dead $9.99 (60% off)
54 Jurassic Park: The Game $7.49 (75% off)
78 Stacking $5.10 (66% off)
83 Tales of Monkey Island $8.75 (75% off)
77 Back to the Future: The Game $6.25 (75% off)
Psychonauts $3.40 (66% off)
Costume Quest $5.10 (66% off)
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Green Man Gaming
55 Game of Thrones $14.99 (50% off)
72 Blood Bowl: Chaos Edition $14.99 (50% off)
Beyond Divinity $4.99 (50% off)
Towns $9.74 (35% off)
Anodyne $6.69 (33% off)
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Get Games
79  Hitman: Absolution $12.49 (75% off)
65 Fuel $3.39 (66% off)
81 Grid $3.74 (75% off)
86  Dirt 3 $8.49 (66% off)
Dirt Showdown $14.99 (50% off)
F1 2012 $13.59 (66% off)
SBK 12 Generations $6.79 (66% off)
Choose two games for $10
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GOG
Up to 80% off D&D titles