i was messing around with my router and trying out an older wireless card to see if i could get it to work with the encryption on my router...i noticed in my router's log that 3 different MAC addresses had connected via wireless. i thought "hmmm, that's funny...i only have 2 wireless cards...".
the foreign MAC didn't get an IP because of my encryption...but i took my laptop for a little walk to see what i could find. i found 4 more WAPs by the time i got to the end of the hallway in my apartment building...that was only on the 1st floor. hahaha
i was using netstumbler. i need to find some other cool apps to use and also get it running on my ipaq for stealth recon.