[Anonymouse]

That is: if you're using a wireless router which isn't secured (in which case you deserve everything you get, you dork!), can you tell if anyone other than you is accessing it? If so, how?

I ask because a friend of mine has a laptop which, as is typical of Vista, insists on being connected to the Internet unless he disables the wireless LAN card - and it keeps picking up on a number of wireless networks, some of which aren't secured. I did point out that this is - I think - illegal, so he asked me if it's possible to tell.

Since I'm not sure, I'm now asking you guys.