If you've been watching for a specific discount, it's probably online somewhere this weekend as digital outfits celebrate Memorial Day with savings on hundreds of titles at Amazon alone, including a tempting $10 pack with Typing of the Dead: Overkill, Space Marine, Aliens vs. Predator as well as two other titles. Meanwhile, Steam offers Dark Souls: Prepare to Die Edition for $6.79 and The Witcher 2 for $3.99, GameStop has Max Payne 3 for $5, Borderlands 2 is $6.80 at GamersGate, and there's plenty happening at the Humble Bundle/Humble Store.

Steam
87 Dark Souls: Prepare to Die Edition $6.79 (66% off)
80  The Witcher: Enhanced Edition Director's Cut $1.99 (80% off)
90 The Witcher 2: Assassins of Kings Enhanced Edition $3.99 (80% off)
86 Warhammer 40,000: Dawn of War - Master Collection $18.99 (50% off)
86 Dawn of War Franchise Pack $69.99 (50% off) 
67 Sniper Elite: Nazi Zombie Army Bundle $6.24 (75% off)
84 Red Faction Collection $14.99 (75% off)
64 Galaxy on Fire 2 Full HD $4.99 (75% off)
74 Typing of The Dead: Overkill $6.79 (66% off)
60 StarDrive $8.99 (70% off)
Viking: Battle for Asgard $3.74 (75% off)
More...

Amazon Digital
77 Ultimate Lego Bundle $45.00 (75% off)
90 Batman Mega Bundle $22.50 (75% off)
75 Don't Die Pack $9.49 (90% off)
83 Metro Pack $12.49 (75% off)
88 Rockstar Ultimate Collection $25.49 (85% off)
83 Saints Row Franchise $18.75 (75% off)
83 Sonic Pack $12.39 (90% off)
80 Firaxis Strategy Pack $42.88 (61% off)
82 Fightin' & Brawlin' Bundle $25.00 (75% off)
80 Risen Franchise Pack $7.99 (80% off)
79 Street Fighter X Tekken Complete Pack $14.99 (75% off)
81 Splinter Cell Pack $26.99 (70% off)
87 Dead Space Pack $17.49 (79% off)
88 Crysis Trilogy $24.99 (50% off)
74 Syndicate + The Saboteur $4.79 (88% off)
88  Total War: Shogun 2 $7.49 (75% off)
90  Super Street Fighter IV: Arcade Edition $7.49 (75% off)
More... (hundreds of deals)

GameStop
86 C&C Collection $4.99 (75% off)
93 Mass Effect Trilogy $9.89 (67% off)
93 TES V: Skyrim $9.99 (50% off)
88 Far Cry 3 $7.49 (75% off)
39 Teenage Mutant Ninja Turtles: Out of the Shadows $3.74 (75% off)
90 Dragon Age Origins: Ultimate Edition $5.99 (80% off)
84 Max Payne 3 $4.99 (75% off)
67 Star Trek $4.49 (70% off)
More...

GamersGate
88 Borderlands 2 $6.80 (66% off -- 4 Pack $20.39, GotY $20.00)
78 Grid 2 Reloaded Edition $25.00 (50% off)
35 Postal 3 $7.49 (75% off)
46 Hard To Be A God $3.74 (75% off)
77 The Bridge $4.00 (60% off)
More...

Green Man Gaming
82 Mafia II Complete Pack $10.59 (80% off)
Air Conflicts Collection $11.24 (75% off)
Citadels $9.99 (75% off)
Disciples Reincarnation $7.49 (75% off)  
Full Bore $7.49 (50% off)
More...

GOG
Teslagrad $6.69 (33% off)
Battle Worlds: Kronos $14.99 (50% off)
70% off Anuman titles