The Pentagon wants to develop small satellites in the 220-330 pound range that could "do useful things" (eavesdrop on communications or relay data for other units). Such satellites are hard to track and the US might, during some future crisis, have dozens of them in orbit with only a few of them known to exist. They can be smuggled into orbit on boosters carrying larger public satellites, or launched on a small booster carried to high altitude by a bomber or heavy cargo plane.--Stephen V Cole