Microsoft has just made available on the Games on Demand service three games. This is Halo 3, the third chapter of the popular FPS Bungie brought to 29.99 euros ( web link ), Saints Row, title sandbox developed by THQ and Volition, available at 19.99 euros ( web link ) and Finally, Sonic The Hedgehog, action game produced by Sega focuses on the adventures of Sonic, the price of 29.99 euros ( web link ).