The Navy League's Sea-Air-Space Exposition is the largest maritime expo in the U.S., and brings together dozens of defense contractors and military decision-makers. The Motley Fool's Rex Moore was at the event in National Harbor, Maryland, and saw demonstrations of several technologies. In the video below he chats with Greg Wallace of Hewlett-Packard (HPQ 0.48%), which manages the 400,000 PCs and cloud-computing network for the Navy and Marine Corps.