Newegg takes up to 83% off a selection of 2K Games Steam downloads for Windows, Mac, and Linux. Plus, coupon code "EMCARNK78" cuts an extra 15% off, slashing starting prices to 84 cents. Combined, that yields all-time price lows on several titles, including the two games below (with prices after coupon):
Newegg offers Steam downloads of BioShock: Triple Pack for Windows for $11.90. Coupon code "EMCARNK78" cuts that to $10.11. That's the lowest price we could find by $46 and within $1 of the best price we've seen. (We saw it for a buck less last month.) This triple pack includes BioShock, BioShock 2, and BioShock: Infinite (also for Mac and Linux).