From the people that invented “Shackles for your computer,” comes something to help liberate it.

Kensington is the standard for locking-up laptops and desktops. But they recently released something to help mobile users on the go find WiFi up to 200 feet away in a small palm-sized device.
Detecting both 802.11b and 802.11g networks, the WiFi Detector can be carried in your pocket and used to find out if you can pull out your laptop and check your email.
It gives status on LED lights, so it doesn’t report on SSIDs and information is somewhat lacking on the website. This obviously cannot be used as a security auditing tool (and there are much better options for that) but may be handy for people that routinely travel and visit various airports.
No pricing is available yet.