In what we assume is an attempt to capitalize on the recent press coverage of Borderlands 2, Steam has cut 75% off all Borderlands content, including the vanilla title, the "Game of the Year" edition and all downloadable content. If you've already explored the dilapidated planet of Pandora, Steam also offers 75% off Counter-Strike, while you'll find 50% off Homefront, Dragon Age 2 and Thief: Deadly Shadows as well as 66% off Civilization V at GamersGate.

Steam
Borderlands: Game of the Year $7.49 (75% off)
Borderlands $4.99 (75% off)
Counter-Strike Complete $7.49 (75% off)
Counter-Strike: Source $4.99 (75% off)
Counter-Strike $2.49 (75% off)
Hector: Badge of Carnage - Full Series $14.99 (25% off)
Day of Defeat: Source $2.49 (75% off)
Day of Defeat $1.24 (75% off)
Hearts of Iron 3 Collection $15.00 (75% off)
Deathmatch Classic $1.24 (75% off)
Ricochet $1.24 (75% off)
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Impulse
Cryostasis $6.49 (50% off)
Evochron Mercenary $10.20 (66% off)
Evochron Legends $6.78 (66% off)
The Tomorrow War $9.99 (50% off)
X3 - Gold $12.49 (50% off)
X3 - Reunion $4.99 (50% off)
X3 - Terran Conflict $9.99 (50% off)
Freespace 2 $19.99 (50% off)
MinerWars 2081 Pre-Alpha $9.35 (36% off)
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GamersGate
Homefront $14.98 (50% off)
Dragon Age 2 $29.95 (50% off)
Sid Meier's Civilization V $16.98 (66% off)
D.W.A.R.F.S $2.50 (50% off)
Divinity II: Flames of Vengeance $9.98 (50% off)
Thief: Deadly Shadows $7.50 (50% off)
Dark Fall: Lost Souls $9.98 (50% off)
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Direct2Drive
Breaking the Rules: The Roman Tournament $2.95 (70% off)

Games for Windows
Europa Universalis III: Chronicles $14.99 (50% off)

Good Old Games
50% off Cyan titles