Less than one week ago, Google announced the Android Device Manager, a native way to locate or ring your Android device directly from within a browser. A day later, a few ADM options started showing up in the Google Play Services app. Today, ADM is completely live and ready to use.
While locating and ringing your devices should be enabled by default, remotely wiping them requires the feature to be activated within Play Services. Past that, it's pretty cut and dry – head here in your browser to give it a shot.