Examples of today's sales include BioShock Infinite ($29.99), Hotline Miami ($2.49), Scribblenauts Unlimited ($4.99), and Call of Juarez: Gunslinger ($10.04).
Meanwhile, flash sales (which last 8 hours before being rotated out) include such stunning deals as Counter Strike: Global Offensive ($5.09), The Elder Scrolls V: Skyrim Legendary Edition ($35.99), Grid 2 ($29.99), and Dragon Age: Origins Ultimate Edition ($8.99).
Check the Steam store for deals. The deal runs from today thru to the 22nd July.
<UPDATE: And this is, of course, the inevitable result of the Summer sale.