Canary Wireless Digital Hotspotter HS-20

This simple and straightforward gadget measures about 3 inches by 2 inches by slightly more than 0.5 inch thick, it's easy to operate one-handed while you walk around. Though it costs more than other signal detectors (which range from key chains to Wi-Fi detectors built into the underside of certain laptops), cheaper devices are rarely designed to identify a network's SSID and encryption status. Canary Wireless says that it "uses a true 802.11 engine, resulting in no false readings from Bluetooth signals, cordless phones, or microwave ovens." My informal tests corroborated this claim. And it's good to know whether a network is open before you pull out your laptop.

My only real criticism of the Hotspotter involves its 30-second automatic shut-off.  Though this quick cutoff may save battery life (the device comes with two AAA batteries), 30 seconds is too short a time. If you get distracted in midscan, the Hotspotter will power down before you're done using it. Also, I would rather be able to see all the relevant details displayed on-screen than have to wait for scrolling text to roll by; still, the most important details show up right away.

Yes, it's yet another gizmo you'll have to remember to pack (and it's largely redundant if you own a Wi-Fi-equipped cell phone), but if you travel frequently with a laptop--or want to check the security status of your company's Wi-Fi networks quickly and easily--the Hotspotter can be a handy tool.