I specifically said, Cory, that it might not make sense for a spammer to look for an open wireless network, but if someone already knew where one was -- say, perhaps someone put up some warchalking symbols -- it'd be mighty tempting. For one thing, an unsecured corporate network probably has at least a T1 behind it, which would sure beat sending millions of messages over a dial-up line. And, while losing a dial-up account is only a minor inconvenience, it's still an inconevience, and if you can get someone else blacklisted instead of yourself, all the better, no? Especially if you can pick up their signal from where you live, then you can do it from your couch.

My point is merely that if you let people use a resource for free, some of them are going to use it for unsavory things. If you know you're providing the resource for free, then you can take steps to prevent abuse, but I'd wager that most people who are providing public wireless access don't know they're doing so.