Social networks aren’t always going to be en vogue. Facebook may have a billion users today, but what happens when that growth stalls? What happens when it turns negative? If it’s no longer the only source of revenue, the answers to those questions matter much less — hence, the purchase of Oculus VR. Lately, Facebook’s been buying (and trying to buy) companies that don’t exactly mesh with what it is. You could look at it two ways: It’s either getting into businesses that it has no concept of how to handle (see: Cisco’s purchase of Flip Video), or either it’s brilliantly diversifying its portfolio.