Earlier this week, Facebook announced that it had acquired Oculus VR for $2 billion, and it turns out that this isn’t the only recent piece of M&A in the category of head-mounted wearable computing. Microsoft, we have discovered, has paid up to $150 million to buy IP assets related to augmented reality, head-borne computers, and related items from the Osterhout Design Group, a low-profile company that develops wearable computing devices and other gadgets, primarily for the military and other government organizations.