SMS Register is WordPress plugin for monetising user registration. If a visitor want to register account on your WP website, he needs to send SMS message following displayed instructions. After that, he will get reply message containing code he needs to enter to apropriate field in registration form.
Now supports BuddyPress! You can charge registration for your BuddyPress members. Plugin will recognize if BuddyPress is active and it will add necessary field to BP registration form. You also can change the style of SMS Register field and SMS sending instructions on BuddyPress registration page.