I thought (don't have it in front of me so I can't check) that you could disable the SSID broadcast, like you can on most routers. If so, that's an easy and quick security feature.
And obviously, change the SSID. That's the very first thing you do with any WiFi router, and your Inc should be no exception. I laugh when I see a network named "linksys" show up under available connections, and I know even without trying that if I browse to 192.168.1.1 I can enter "admin" for both the username and password and be into their admin setup. Not that I would ever do that.