Does the external ip address no longer show in your iStat Pro widget? Here's one way to fix this problem, as it appears that islayer has stopped running their "FindMyIP" service, so open this file in a code editor:
Note that you will have to restart the iStat widget by either using "-" and "+" to re-add it, or just hold down Command-R while clicking on a Widget. They'll spin like a black hole and restart.