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Bundle Stars has the All Stars Bundle on sale at their site. The bundle is $1.99 for the first 24 hours then it goes up to $2.99.
Includes:
Tropico 4 Steam Special Edition
Magicka
S.T.A.L.K.E.R: Clear Sky
Mount & Blade: With Fire And Sword
System Shock 2
Deponia
To The Moon
Prime World: Defenders