Steam cuts up to 90% off a selection of downloadable games and game DLC for Windows or Mac during its Summer Sale, with prices starting at 24 cents. It also offers a selection of daily deals and flash deals. That ties yesterday's mention as the largest sale we've seen from Steam in over a year and puts many titles at the lowest prices we've seen. New flash deals happen every eight hours, and the current selection of daily deals ends today at 1 pm ET.

A best bet is downloads of System Shock 2 for Windows for $2.49. That's $5 under our May mention and the lowest price we could find for this classic FPS-RPG.

Of note, Amazon is currently matching many of these prices.