I made my own service with a free Google App Engine instance, using this script as a base → <a href="https://github.com/danawoodman/python-uptime-monitor" rel="nofollow">https://github.com/danawoodman/python-uptime-monitor</a> mainly to use the SMS gateway api from my provider.<p>Simple enough, write the views and use the cron service from GAE, for myself 2secods it's more than efficient.<p>I will never hit any cost on GAE just monitoring 12 servers every 2 seconds.<p>You will get more capabilities, writing your own uptime script and personally I will add: it's more fun :-)