Collecting their MAC address is easy. I just type in the host IP address into a web browser, and BINGO, I have their router up, including the MAC addresses of all the users logged onto their network (plus I can get any other ones through sys logs).
And, to counter the 2Wire sucks thing- they aren't great, but they don't drop signal as badly as this router does. I can lose my connection even when I'm at 60% signal strength, and sometimes it won't even show up as an available network (but their router is still on- see above comment about checking logs).
Also, I wasn't seriously considering locking them out of their own network. I would be better off locking everyone else OUT, so they wouldn't need to remember any passwords.
Plus, the router isn't configured. There IS no password, not even a default, that I know of. I did encrypt it one time at like, 3AM so I would know they weren't up, and I tried DHCP filtering with just my MAC at the same time. Both were done without entering a password to change settings. If there was a default, it was only used to intially set the router up.
There are over 200 unsecured networks in my city, and most of them are also with people using XP's networking with Shared Documents. Anyone with a laptop and free time could have all sorts of exploitation-related fun.
Side note: The Geek Squad in my area was running of an unencrypted network for a while. Not only did they keep all their service logs as Shared Documents, but the Game Crazy 200' away was running part of their network off of the signal. It took almost 6 months for GS to figure out why all their customers were getting prank calls about their computer's performance being slowed down by kiddy porn and how they would go over bandwidth limits when the network computers weren't even being used.