I have written two modules for Google's personalized home page, iGoogle. 

MRTG Graphs:
This module pulls in your MRTG graphs. It will display whichever graph is your index by default, and also include links to show the others.

Server Status:
A module which shows the status for different services on your server. It is designed to be flexible and easily extensible so that you can write your own tests. The module is released with tests for MySQL, SMTP, free disk space and some basic process information.