Situation: my wife's iPhone 4 has been connected (voluntarily, by my wife - using the "ask to join" setting) to pretty much any open wifi hotspot she happened to be near, including random homes and businesses, etc. She told me she was doing that to cut down on 3G usage.. Anyway, I'd like to go in and knock those all out of those networks. I don't want her phone signing into "linksys" and other similar networks just because she did so once a few weeks ago. However, I can't see a way to "forget" these networks without actually driving around town looking for the networks to forget. Help?