Darn, I thought they meant some kind of swimming pool, not an amphibious infantry vehicle. Read Wired and visit VehicleFORGE
The Pentagonâ€™s blue-sky researchers are gambling that you can build a swimming tank for the Marines in a fraction of the time it takes the militaryâ€™s lumbering acquisitions process. All you need are the relevant data and a set of web-based collaborative tools. And its gamble will pay you a million dollars if youâ€™re part of the winning design team.