When this laptop I have wakes up after being asleep, sometimes it goes wireless using someone's network in my apartment complex.
It does this even though I don't have any kind of wireless router or anything. I have a straight hookup from the modem to the laptop using an ethernet cable.
Someone that knows computers but doesn't know about Windows 7 said to hit the F8 key that has an antenna above it to tell it not to go wireless. That might work but I have the laptop hooked up to a 24" external monitor and if I leave the lid open or open it back up while the computer is on, it won't go to the monitor. If that makes any sense.