For today, and only today, Sonic the Hedgehog 1, 2 and 3, and Sonic and Knuckles are all 240 Microsoft Points on the Xbox 360 Marketplace in celebration of 19 years of Sonic videogames. Sonic the Hedgehog 4: Episode 1, a return to the game’s 2D roots after years of dabbling in 3D adventures, will be available for download on Xbox Live Arcade in the latter half of 2010.