KnownOutage is the perfect solution for smaller teams, such as webhosts, IT staff, or anyone who needs to alert people when there is a problem. KnownOutage Lite will allow a single administrator to have unlimited "services" (items to be tracked, like servers, offices, networks, etc). An unlimited number of people can subscribe to these services, and if there is an issue, the administrator can quickly and easily communicate this to the users.
The administrator can log alerts to the system when a problem is detected, isolated, and resolved.
These alerts can be web only, or can include an email to all subscribed users.
Incident history is kept indefinitely, so trends are easy to spot.
KnownOutage Lite is a PHP / mySQL script that runs on your server, so you'll have full control of it. You can keep this internal, for employees only, or you can put this on the internet, and have anyone access it over the internet.