I've decided to release version 1.5 of Server Ping as a paid-for gadget as there is quite a lot of interest for a version that can support more than 5 servers. Below is a table of the features showing the difference between the two versions and a PayPal button. Once you click the PayPal button this will take you to a payment page, once you complete payment I'll email you the link to download the gadget.
The main difference between the two is the Pro version supports up to 50 servers and is scaleable and auto-resizes.
EDIT: Server ping pro now supports different thresholds for Green and Orange LEDs showing how long the server takes to respond to pings