WiFi Hopper is great for sniffing out any nearby networks, as well as for getting a great deal of information about them, to make it easier to decide whether you should connect. It scans for Wi-Fi networks and it reports, for each of them, the SSID (network name), the MAC address of the wireless router, the signal strength, whether the network is encrypted, the type of encryption, your connection status, the frequency on which the network operates, and more.
It also reports whether the network is in infrastructure mode (where you're connected to a wireless router), or ad hoc mode (a PC-to-PC connection). Ad hoc connections are potentially dangerous, so you should stay away from them unless you know the person whose machine you'll connect to.
On top of all that is another nice extra: you can view a graph of the signal strength, in real time, of any nearby network. And to connect to any network that WiFi Hopper finds, you simply double-click it. WiFi Hopper is available as a 30-day free trial.
Wireless Wizard is a freebie designed to work with the Wi-Fi provider Azulstar, which runs municipal networks throughout the US, but it's even useful for people who aren't Azulstar customers. It displays information about your current wireless connection, including the SSID, the signal strength, the access point channel, the gateway, the domain of your Internet provider, and much more. It also offers a set of troubleshooting tools, checking for any problems with your IP address, signal strength, and so on.
It's generally useful, but it also makes mistakes on occasion, for example, it might report that you have poor wireless link quality, when in fact the connection is good. Still, you can't argue with free.
Don't like to carry around a dedicated GPS device? No problem. Turn your laptop into your navigator with this very clever toolbar, which works in both Internet Explorer and Firefox. It employs triangulation technology with any Wi-Fi connections near you to determine your location in concert with its Wi-Fi Positioning System. In addition, it will show you nearby movies, shopping, traffic, weather, and so on via various channels, though the channels often appear in a separate browser window.
Be prepared to be offended (or entertained) by some channels, such as the one that shows nearby strip clubs for both men and women. And I discovered that the channel information isn't always particularly helpful, for instance, the restaurants channel showed me establishments located miles away rather than those nearby. Still, the channels are of some use.
Loki Toolbar functions as a social networking tool, too. You can choose to have your location shown to other people, and see their location, so that you can connect with them in the real world.