netmeg - 2:59 pm on May 25, 2007 (gmt 0)

I can't swear to it, but I have a feeling that Google compares the IP numbers of where you log in to your AdSense account to the click IPs to determine whether or not to discount the accidental click. Only thing I can think of, because I've had stray accidental clicks over the years, and I have one IP number at home and two at work that are fairly static, and they NEVER have counted any earnings to a one of my accidental clicks - and I have logged in to the AdSense console from all three places at different times.

How that works for people with dialup and AOL, I have no idea. All I know what I've seen myself.