I did this, and most of them still require some sort of purchase. I'm willing to purchase one if its cheap, but i'm just trying to see if anyone has experience using them with their company and how much they like them.Why don't you try searching for something like "Open source network notification application" and see what comes up. Open source software is typically free. The wording of the search should say as much as it can about what you actually want to do. Sometimes re-wording the search in some way can give you other options to look at.