The Objective Individual Combat Weapon or OICW is the US Army's response to the most modern advances in weapons technology.  It combines a standard NATO 5.56mm rifle accurate to 1,000 meters with a 20mm High-Explosive launcher.  Both are highly accurate and can be used separately or with each other (reccomended).  It will become common in 2005 and will replace the M16 and M203 grenade launcher.  For more information, see Pop. Sci. Magazine, July 1998 issue.