Caller ID from WhitePages is an add-on for the default Android caller ID that enables location detection. The service tells you two bits of info whenever someone (whether they're on your contact list or not) calls: the approximate city the number belongs to and whether or not it's a landline. The app seems to work pretty well for the first (it got my phone's area correct), but wasn't smart enough to know that it wasn't a landline I was calling from. Still, a pretty useful app for those weird numbers you get sometimes. Available now on the Android Marketplace.