If you live near a Target, they're supposed to update their clearance prices on Mondays.
Prices aren't going to be the same across the board at every Target, but right now the big titles that are on clearance include Battlestations: Pacific, FEAR 2, HAWX, Mortal Kombat vs. DC Universe and The Chronicles of Riddick: Dark Athena for the 360; and FEAR 2, Tomb Raider: Underworld, Guitar Hero: World Tour and Motorstorm: Pacific Rift for the PS3.
If you're really lucky, you'll find Left 4 Dead for less than $15 and Ninja Blade for less than $10. Some Targets are selling the PS3 Endwar bundled with a Bluetooth for under $25. I found a Riddick: Dark Athena at my local Target for $15.