<br /><br />I love borrowed internet when I travel... just used to check iboats then continue on down the road anyway. Now I have wirelss but its much slower than cable and if I have lotsa stuff to check i'll find a non secure connection to borrow. I figure if they leave it open for me, that no harm done in borrowing. Oh and I never do anything harmful with it. 
<br /><br />Xcusme makes some very good points. Also, I would make sure (or at least hope) that the network you are joining isn't being watched or owned by a hacker. The risk is probably low, but the consequenses would be high. I tend to be a bit paranoid with that kind of stuff and usually stay away.
Well, there's 2 ways that come to mind. First, login into your router by launching your web browser (MIE-Firefox etc). Enter the IP of your router on the URL address line (ex: 192.168.1.1 or 192.168.1.0 etc). This will open the login dialog box. Enter your login and password (you did change it from the defaults--I Hope!!) In the menus, you should find a status screen. Look for wireless clients. It should show you any and all wireless MAC addresses that are connected thru your router. You should keep a listing of YOUR MAC addresses for reference. Every wireless adaptor has a MAC address. If you see strange MAC addy's connected, someone's free loading on your connection.<br /><br />The second way to watch your wireless system is to install a utility that watches for you. Google for Airsnare...d/l same and install. Read the docs and setup the program (easy- when you read the documentation). When someone accesses your wireless router, you'll be notified with a voice saying "Wireless access detected". <br /><br />There are numerous programs to monitor your router, depending on the make of your router.
This is pretty simple. If you have a wireless router, you should have setup your own SSID (name of your wireless 'station'). The default SSID for different makes of routers are different. Some broadcast, 'Default' others 'Linksys' , you get the idea.<br /><br />If you've changed your wireless SSID to say 'stargate' and Windows shows that you are connected to any other SSID, then you are leeching off of someone else's wireless router.<br /><br />When I see a wireless AP with the 'default' SSID, I figure that the guy didn't bother changing the routers' login and password either, let alone, turning on any kind of protection.<br /><br />The router companies are trying to make things easy for folks that buy their equipment by NOT turning on the built-in security features. Just plug it in and go...but that's the problem, it's too easy for others to use it too.<br /><br />BTW, WEP codes can be cracked in about 10 minutes...WPA is much better. Turn WPA on in your router, add a strong passphrase. Goto your laptop, enable WPA in the client manager, adding the same strong passphrase and you're good to go.
