^Yup. That's the one. 4wd beat me to it.

Things like this can keep sysadmins up at night since the same thing could be used for much more nefarious purposes like setting up 'man in the middle' type spoofs, hiding secret file servers (linked to a Dropbox account), planting remotely controlled timebomb machines to gum up the internal network with bogus packets (watch the IT dudes go crazy trying to figure out how the packets are supposedly making it in
through the firewall), ...oh...the mind boggles. Especially since end-to-end encryption is the exception rather than the rule in most places. LANs tend to be pretty open and less monitored than the WAN and gateway traffic usually is. Once you're in - you're *IN* - on many LANs. And a so-called passive sniffing setup is also very doable, making these things very hard to detect.
A couple of night cleaning people armed with a handful of these babies to leave behind could 'clean' a lot more than just the wastebaskets and rugs.
Oh well! There's no rest for the wicked. One
more thing to be aware of. And check for.
