SiteCatalyst has an "Alerts" feature that allows users, based on a metric exceeding a specific point, to send alerts via email to various people.
This would be perfect for monitoring errors on the site (404/Page Not Found). I set up an alert this week to try it out, but was disappointed that there's no option to include any text with the email. It comes across as a cryptic message from SC with an attachment. We should be able to customize the message for any Alert we create, e.g. "Omniture has detected a large number of 404 errors on [site name]. You can investigate further by logging and reviewing the Pages Not Found report inside SiteCatalyst.")