But this $70
Digital Wi-Fi Detector
from Think Geek is a little more eloquent in its communication. Besides telling you, on its backlit LCD screen, whether or not you’re in range of a network (in its case, from up to 200 feet away), it’ll also tell you the network’s name (SSID), the signal strength, the channel, and whether the network is using encryption (WEP or WPA). You can scroll through all the available networks, should you be in a particularly
It works with both 802.11 b and g networks, and runs on a pair of included AAA batteries. And to keep those from running down, it’ll auto power off if you haven’t used it in awhile. Best of all, at 2.5″ x 2.75″ x 1″ thick, it won’t take up a lot of extra space in your laptop bag.