We use PagerDuty where I work at Care.com to manage on-call notifications, escalations, etc. It's a great tool to manage alerts from tools and services like Nagios, New Relic, and dozens of others. They also provide a handy dandy REST API, and it should be no surprise that somebody then wrote a Python module to encapsulate it (thanks DropBox!). Thanks to that I wrote a handy-dandy command line tool called pdmaint for my company to schedule maintenance windows in PagerDuty. Since we've found it incredibly useful I was able to get the powers-that-be to let us open source it. So you can find pdmaint over at Github if you're interested. There's a full set of documentation there as well.