Noah Shachtman, defense editor for the Wired blog network, uncovered a 2004 request from the Marines for a Marine Exoskeletal Performance Augmentation Capability. Called MEAC for short, the gear would protect troops today and eventually, maybe, develop into a "self-aware" machine with no need for a human attachment.
Shachtman writes that the Marines' proposal appears to have gone nowhere, but the idea may have resurfaced elsewhere:
[O]ther parts of the military continue to pursue exoskeletons. According to Pentagon budget documents, a project to build a "personal combat vehicle," allowing a soldier to "carry 150 pounds while feeling only a small part of the load" is making its way from the blue-sky technologists at Darpa to the Army's more practically-focused engineers.