The OS X 10.5 Address Book application has a feature to import contacts from Gmail. However, this means all contacts, including ones without phone numbers. If you've had an email account for a long time, there are going to be all sorts of "contacts" in there, like mailing lists. So I needed to prune away all entries without phone numbers. Turns out in new OS X versions, you can restrict to a group of contacts, but not so in my version.
So I wrote a little AppleScript script to do it. Feel free to try it, but be sure to make an export/backup of your Address Book before you do.
An ERROR has occured!
Here you might send email-notification to webmaster or something like that.