The guys over at have finally released their XNA engine called Torque X and their tool set called Torque X Builder. Torque X comes in 2 flavors, standard and a professional edition. The standard is free, and the profession costs some money (depending if you are indie or commercial), but the profession does include the source code. The tool set Torque X Builder is free for the users that have subscribed to the XNA Creators Club, otherwise it is a 30 day free trial, and then costs a bit (again, depends on if you are an indie or a commercial dev). Lastly, they have released a Platformer starter kit for the Torque X engine. For more information, check out here.