We are migrating from Cacti to Observium and it was a great experience, the only thing we lacked were the weathermap plugin for getting that nice network overview.

I then found that Neil Lathwood wrote a modified version of the PHP Weathermap that works with Observium data, you can find it on his github: https://github.com/laf/weathermap

I wrote a quick and dirty script that adds the weathermaps to the Observium menu without modifying Observium-code so that it will not break when updating Observium.

It works really well so I wrote a little guide for how you get the weathermap to work with Observium and posted it here: 

In case there are more people interested in using the weathermap with Observium :)

/Markus