Steam - Dog Fighter $1.50 (85% Off) & THQ Week - Titan Quest Gold $3.74 (75% Off)

PC Game - Looks like fun for $1.50 (NOTE: Prices in US Dollars)

DogFighter is a fast paced, arcade aerial combat game with arena style gameplay values. Players can compete against up to 15 opponents in 4 multiplayer modes, or go solo in 7 single player game modes, using beefed up biplanes sporting over 20 different offensive and defensive weapons…
… and that’s just the start.

THQ Week - Daily sales:

WEDNESDAY -
Titan Quest Gold - Includes Titan Quest and Titan Quest - Immortal Throne
http://store.steampowered.com/sub/1123/

TUESDAY - ENDED
Red Faction I & II $2.49 & Guerrilla $17.49 75% Off:
http://store.steampowered.com/sale/redfaction