There's a post sitting in my drafts about Wireshark and how to sniff packets out of the air that was going to be about sniffing for authentication packets for Wi-Fi hotspots that aren't broadcasting SSID (Which you shouldn't do apparently! It's still not safe). I was watching this video to find a little more information about how to properly use Monitoring mode on my Macbook to sniff for WLAN packets on the network. So when he said "Just open up Wireless Diagnostics and sniff your network (check your width and channel)." It was shocking to me.