The Dude Network Monitor

This is free of charge.

"The Dude network monitor is a new application by MikroTik which can dramatically improve the way you manage your network enviroment. It will automatically scan all devices within specified subnets, draw and layout a map of your networks, monitor services of your devices and alert you in case some service has problems."

http://www.mikrotik.com/thedude.php

Thanks! That looks sweet, gonna try it out tomorrow.

Thanks ecross, it looks like a realtively easy product to get installed and up and running.

Personally I use MRTG with multiple front ends and also utilize WeatherMap to geographically plot device locations for visual representation. It too is free, and can be found here ...

http://oss.oetiker.ch/mrtg/

The setup and installation of MRTG is much more complex than just installing an app and tuning it to your devices. However, it's script loaded so you can tweak it much more than a canned solution.