Wi-Fi device detection

Some devices broadcast their own and aren't necessarily connected to anything else.

Wireless printers come to mind. They broadcast an unsecured SSID so you can connect to them and install the drivers via that connection.
AND these devices are a big security hole behind your firewall!! A common easy way into firewalled networks! I worked for AT@T and we had our meeting room in a Central office building. The guys wanted to connect there devices wireless, so one of them set up a Wirless Acees point. Connected with ethernet to the Secured, VERY secured AT@T network. THE most secured network behind the pentagon in the country. OMG. The **** I got into, allowing that!! All you had to do is hack the simple password for the WAP, and you were behind millions of dollars of firewalls!!! Was not a good day for me. I did not know about printers, the same issue...